diff --git a/crates/engine/src/commands/file_more.rs b/crates/engine/src/commands/file_more.rs
index 9aecd8d6..ca170cc1 100644
--- a/crates/engine/src/commands/file_more.rs
+++ b/crates/engine/src/commands/file_more.rs
@@ -848,14 +848,32 @@ fn replace_footage(s: &mut Session, p: &Value) -> Result<Value> {
     let src = crate::sequence::source_of(s.services.as_ref(), &path, opts);
     let f = crate::sequence::probe(importer.as_ref(), &src, s.sequence_rate()).map_err(|e| EngineError::Other(format!("{path}: {e}")))?;
     let name = src.name();
+    // Replacing a missing file relinks the other missing files that moved with it (as After Effects
+    // does when you locate one).
+    let moved = match s.project.item(item).map(|it| &it.kind) {
+        Some(ItemKind::Footage(previous)) if previous.missing || !s.services.exists(&previous.path) => {
+            super::relink_moved::moved_with(s, item, &previous.path, &path)
+        }
+        _ => vec![],
+    };
+    let relinked: Vec<u64> = moved.iter().map(|(id, _)| id.0).collect();
     s.edit("Replace Footage", None, |proj, _| {
         let it = proj.item_mut(item).ok_or_else(|| bad("file.replaceFootage", "no such item"))?;
         it.name = name;
         it.kind = ItemKind::Footage(f);
         retarget_layers(proj, item, |_| LayerSource::Footage { item });
+        for (id, nf) in moved {
+            if let Some(it) = proj.item_mut(id) {
+                it.kind = ItemKind::Footage(nf);
+            }
+        }
         Ok(())
     })?;
-    Ok(Value::Null)
+    if relinked.is_empty() {
+        return Ok(Value::Null);
+    }
+    s.toast(format!("Also relinked {} other missing footage item(s)", relinked.len()));
+    Ok(json!({"relinked": relinked}))
 }
 
 /// Point every layer using `item` at a new source kind.
diff --git a/crates/engine/src/commands/mod.rs b/crates/engine/src/commands/mod.rs
index 98fe0cb4..0a27d473 100644
--- a/crates/engine/src/commands/mod.rs
+++ b/crates/engine/src/commands/mod.rs
@@ -49,6 +49,7 @@ mod proxy;
 pub mod puppet;
 mod query;
 mod relink;
+pub(crate) mod relink_moved;
 mod render_queue;
 pub(crate) mod rig3d;
 pub mod roto_cmds;
@@ -171,6 +172,7 @@ pub fn command_specs() -> &'static [CommandSpec] {
         v.extend(key_transform::specs());
         v.extend(file_more::specs());
         v.extend(relink::specs());
+        v.extend(relink_moved::specs());
         v.extend(lottie::specs());
         v.extend(timeline::specs());
         v.extend(comp_more::specs());
diff --git a/crates/engine/src/commands/relink_moved.rs b/crates/engine/src/commands/relink_moved.rs
new file mode 100644
index 00000000..4f70dd6e
--- /dev/null
+++ b/crates/engine/src/commands/relink_moved.rs
@@ -0,0 +1,319 @@
+//! Relinking footage that moved together (gaps.md G4; After Effects' Replace Footage on a missing
+//! file, which then finds the other missing files in the same place). Searching a folder for
+//! compatible files is `file.relinkFootage` ([`super::relink`]).
+//!
+//! - `footage.relink {item, path}`: point a footage item at `path`, keeping its interpretation, and
+//!   relink every other missing item that sits in the same place relative to it (the folder moved,
+//!   or a drive was renamed). One undo step. Replace Footage on a missing item does the same.
+//! - `footage.missing`: the missing items.
+//! - When a project opens from a folder it wasn't saved in, the footage check ([`moved_candidates`])
+//!   tries each missing file at the same place under the project's new folder.
+//!
+//! Paths are compared by their parts, split on `/` and `\`, so a project made on Windows relinks on
+//! macOS and the other way round.
+
+use effectcraft_project::{Footage, FootageKind, ItemId, ItemKind, Project};
+use serde_json::{Value, json};
+
+use super::{CommandSpec, bad, str_p};
+use crate::{Result, Services, Session, cmd};
+
+/// Trailing parts of a path tried under a moved project's folder.
+const MOVED_PARTS: usize = 4;
+
+fn parts(path: &str) -> Vec<&str> {
+    path.split(['/', '\\']).filter(|p| !p.is_empty()).collect()
+}
+
+/// The separator `path` uses (Windows paths keep theirs).
+fn sep_of(path: &str) -> char {
+    if path.contains('\\') && !path.contains('/') { '\\' } else { '/' }
+}
+
+fn file_name(path: &str) -> &str {
+    parts(path).last().copied().unwrap_or("")
+}
+
+/// `prefix` and `rest` joined with `prefix`'s separator.
+fn join(prefix: &str, rest: &[&str]) -> String {
+    let sep = sep_of(prefix);
+    let mut out = prefix.trim_end_matches(['/', '\\']).to_string();
+    for p in rest {
+        out.push(sep);
+        out.push_str(p);
+    }
+    out
+}
+
+/// What moved: `old` became `new`. The parts they end with in common are the same file's place
+/// inside the moved folder; what comes before is the folder's old and new location.
+/// `("/a/b/shots/x.mov", "/c/shots/x.mov")` → `(["a", "b"], "/c")`.
+fn moved_root<'a>(old: &'a str, new: &str) -> Option<(Vec<&'a str>, String)> {
+    let (o, n) = (parts(old), parts(new));
+    let common = o.iter().rev().zip(n.iter().rev()).take_while(|(a, b)| a == b).count();
+    // At least the file name must match, else it's a different file (then only its folder moved).
+    let common = common.max(1).min(o.len()).min(n.len());
+    let old_root: Vec<&str> = o.get(..o.len() - common)?.to_vec();
+    // The new root keeps a leading `/` or a drive letter as written.
+    let new_parts = n.len() - common;
+    let mut new_root = String::new();
+    if new.starts_with('/') {
+        new_root.push('/');
+    } else if new.starts_with("\\\\") {
+        new_root.push_str("\\\\");
+    }
+    let sep = sep_of(new);
+    for (i, p) in n.iter().take(new_parts).enumerate() {
+        if i > 0 {
+            new_root.push(sep);
+        }
+        new_root.push_str(p);
+    }
+    Some((old_root, new_root))
+}
+
+/// `path` under the moved root, when it was under the old one.
+fn remap(path: &str, old_root: &[&str], new_root: &str) -> Option<String> {
+    let p = parts(path);
+    if p.len() <= old_root.len() || p.get(..old_root.len())? != old_root {
+        return None;
+    }
+    Some(join(new_root, p.get(old_root.len()..)?))
+}
+
+/// The item's file and, for an image sequence, every frame, moved by `f`; `None` unless its main
+/// file maps.
+fn moved_footage(footage: &Footage, f: impl Fn(&str) -> Option<String>) -> Option<Footage> {
+    let mut nf = footage.clone();
+    nf.path = f(&footage.path)?;
+    nf.sequence = footage.sequence.iter().map(|p| f(p).unwrap_or_else(|| p.clone())).collect();
+    nf.missing = false;
+    Some(nf)
+}
+
+fn present(s: &dyn Services, f: &Footage) -> bool {
+    !f.path.is_empty() && s.exists(&f.path)
+}
+
+/// Footage items whose file is gone (flagged by the footage check, or not there now).
+fn missing_items(s: &Session) -> Vec<(ItemId, Footage)> {
+    s.project
+        .items
+        .values()
+        .filter_map(|i| match &i.kind {
+            ItemKind::Footage(f) if f.kind != FootageKind::Data && !f.path.is_empty() && (f.missing || !present(s.services.as_ref(), f)) => {
+                Some((i.id, f.clone()))
+            }
+            _ => None,
+        })
+        .collect()
+}
+
+/// Where a file a moved project lost may be now: the same place under the project's new folder,
+/// trying the longest tail of its old path first (`/old/proj/shots/a.mov` with the project now in
+/// `/new/proj` → `/new/proj/old/proj/shots/a.mov`, …, `/new/proj/shots/a.mov`, `/new/proj/a.mov`).
+pub(crate) fn moved_candidates(project_dir: &str, path: &str) -> Vec<String> {
+    let p = parts(path);
+    (1..=MOVED_PARTS.min(p.len())).rev().filter_map(|k| p.get(p.len() - k..)).map(|tail| join(project_dir, tail)).collect()
+}
+
+/// A missing item found again under a moved project's folder ([`moved_candidates`]), with its
+/// sequence frames moved alongside.
+pub(crate) fn find_moved(services: &dyn Services, project_dir: &str, f: &Footage) -> Option<Footage> {
+    moved_candidates(project_dir, &f.path).into_iter().filter(|c| services.exists(c)).find_map(|hit| {
+        let (old_root, new_root) = moved_root(&f.path, &hit)?;
+        moved_footage(f, |q| if q == f.path { Some(hit.clone()) } else { remap(q, &old_root, &new_root) })
+    })
+}
+
+/// The folder a project file is in.
+pub(crate) fn project_dir(project_path: &str) -> Option<String> {
+    let p = parts(project_path);
+    if p.len() < 2 {
+        return None;
+    }
+    let mut dir = join(if project_path.starts_with('/') { "/" } else { "" }, p.get(..p.len() - 1)?);
+    if !project_path.starts_with('/') {
+        dir = dir.trim_start_matches(['/', '\\']).to_string();
+    }
+    Some(dir)
+}
+
+/// Relink `found` in one undo step and say how many.
+fn apply(s: &mut Session, label: &str, found: Vec<(ItemId, Footage)>) -> Result<Value> {
+    if found.is_empty() {
+        return Ok(json!({"relinked": [], "stillMissing": missing_items(s).len()}));
+    }
+    let ids: Vec<u64> = found.iter().map(|(id, _)| id.0).collect();
+    s.edit(label, None, |proj: &mut Project, _| {
+        for (id, nf) in found {
+            if let Some(it) = proj.item_mut(id) {
+                it.kind = ItemKind::Footage(nf);
+            }
+        }
+        Ok(())
+    })?;
+    s.events.push(crate::Event::PurgeCaches);
+    let still = missing_items(s).len();
+    s.toast(match still {
+        0 => format!("Relinked {} footage item(s)", ids.len()),
+        n => format!("Relinked {} footage item(s); {n} still missing", ids.len()),
+    });
+    Ok(json!({"relinked": ids, "stillMissing": still}))
+}
+
+/// The other missing items that moved the way `item` did (`old_path` → `new_path`): the same place
+/// under the moved folder, else the same name in the new file's folder. Used by `footage.relink`
+/// and by Replace Footage on a missing item.
+pub(crate) fn moved_with(s: &Session, item: ItemId, old_path: &str, new_path: &str) -> Vec<(ItemId, Footage)> {
+    let Some((old_root, new_root)) = moved_root(old_path, new_path) else { return vec![] };
+    let services = s.services.clone();
+    let new_dir = project_dir(new_path);
+    let mut found = vec![];
+    for (id, f) in missing_items(s) {
+        if id == item {
+            continue;
+        }
+        let same_place = moved_footage(&f, |q| remap(q, &old_root, &new_root)).filter(|nf| present(services.as_ref(), nf));
+        let same_folder = || {
+            let dir = new_dir.as_deref()?;
+            let dir_parts = parts(dir);
+            let old_dir_len = parts(&f.path).len().checked_sub(1)?;
+            let old_dir: Vec<&str> = parts(&f.path).get(..old_dir_len)?.to_vec();
+            moved_footage(&f, |q| remap(q, &old_dir, dir).or_else(|| Some(join(dir, &[file_name(q)])))).filter(|nf| {
+                // Only frames in that one folder (a name match, not a guess deeper down).
+                present(services.as_ref(), nf) && parts(&nf.path).len() == dir_parts.len() + 1
+            })
+        };
+        if let Some(nf) = same_place.or_else(same_folder) {
+            found.push((id, nf));
+        }
+    }
+    found
+}
+
+/// `footage.relink {item, path}`
+fn relink(s: &mut Session, p: &Value) -> Result<Value> {
+    const CMD: &str = "footage.relink";
+    let path = str_p(p, "path").filter(|p| !p.trim().is_empty()).ok_or_else(|| bad(CMD, "missing `path` (the file's new location)"))?.to_string();
+    let item = p.get("item").and_then(Value::as_u64).map(ItemId).ok_or_else(|| bad(CMD, "missing `item` (a footage item id)"))?;
+    let Some(ItemKind::Footage(old)) = s.project.item(item).map(|i| &i.kind) else { return Err(bad(CMD, "`item` is not a footage item")) };
+    let old = old.clone();
+    if !s.services.exists(&path) {
+        return Err(bad(CMD, format!("there is no file at {path}")));
+    }
+    let (old_root, new_root) = moved_root(&old.path, &path).ok_or_else(|| bad(CMD, "cannot compare the old and new paths"))?;
+    // The item itself: its file is `path`; its sequence frames move with it.
+    let main =
+        moved_footage(&old, |q| if q == old.path { Some(path.clone()) } else { remap(q, &old_root, &new_root) }).ok_or_else(|| bad(CMD, "cannot relink"))?;
+    let mut found = vec![(item, main)];
+    found.extend(moved_with(s, item, &old.path, &path));
+    apply(s, "Relink Footage", found)
+}
+
+/// `footage.missing`: the missing footage items and where they were.
+fn missing(s: &mut Session, _: &Value) -> Result<Value> {
+    let list: Vec<Value> = missing_items(s)
+        .into_iter()
+        .map(|(id, f)| json!({"item": id.0, "name": s.project.item(id).map(|i| i.name.clone()).unwrap_or_default(), "path": f.path}))
+        .collect();
+    Ok(json!({"missing": list}))
+}
+
+fn has_footage(s: &Session) -> std::result::Result<(), String> {
+    if s.project.items.values().any(|i| matches!(i.kind, ItemKind::Footage(_))) { Ok(()) } else { Err("the project has no footage".into()) }
+}
+
+pub fn specs() -> Vec<CommandSpec> {
+    vec![
+        cmd!(
+            "footage.relink",
+            "Relink Footage",
+            [],
+            None,
+            "{item, path} — point a footage item at its file's new location (keeps the interpretation) and relink the other missing files found in the same place",
+            has_footage,
+            relink
+        ),
+        crate::query!("footage.missing", "Missing Footage", "{} → {missing: [{item, name, path}]}", missing),
+    ]
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn moved_roots_and_remaps() {
+        let (old, new) = moved_root("/a/b/shots/x.mov", "/c/shots/x.mov").unwrap();
+        assert_eq!((old, new.as_str()), (vec!["a", "b"], "/c"));
+        assert_eq!(remap("/a/b/shots/y.mov", &["a", "b"], "/c").as_deref(), Some("/c/shots/y.mov"));
+        assert_eq!(remap("/a/z/y.mov", &["a", "b"], "/c"), None);
+        // Windows to macOS.
+        let (old, new) = moved_root("D:\\Work\\Job\\audio\\m.wav", "/Volumes/Work/Job/audio/m.wav").unwrap();
+        assert_eq!((old, new.as_str()), (vec!["D:"], "/Volumes"));
+        assert_eq!(remap("D:\\Work\\Job\\img\\a.png", &["D:"], "/Volumes").as_deref(), Some("/Volumes/Work/Job/img/a.png"));
+        // A different file name: only the folder moved.
+        let (old, new) = moved_root("/a/x.mov", "/b/y.mov").unwrap();
+        assert_eq!((old, new.as_str()), (vec!["a"], "/b"));
+        assert_eq!(
+            moved_candidates("/new/p", "/old/p/shots/a.mov"),
+            ["/new/p/old/p/shots/a.mov", "/new/p/p/shots/a.mov", "/new/p/shots/a.mov", "/new/p/a.mov"]
+        );
+        assert_eq!(project_dir("/x/y/p.ecproj").as_deref(), Some("/x/y"));
+        assert_eq!(project_dir("p.ecproj"), None);
+        // Hostile input doesn't panic.
+        for (a, b) in [("", ""), ("/", "/"), ("x", ""), ("\\\\", "//"), ("/a", "/a/b/c")] {
+            let _ = moved_root(a, b);
+            let _ = moved_candidates(b, a);
+            let _ = project_dir(a);
+        }
+    }
+
+    fn temp(name: &str) -> std::path::PathBuf {
+        let d = std::env::temp_dir().join(format!("ec-relink-{name}-{}", std::process::id()));
+        let _ = std::fs::remove_dir_all(&d);
+        d
+    }
+
+    fn add(s: &mut Session, path: &str) -> ItemId {
+        let f = Footage { path: path.into(), width: 8, height: 8, has_video: true, missing: true, ..Default::default() };
+        std::sync::Arc::make_mut(&mut s.project).add_item(file_name(path), crate::color::Label::None, None, ItemKind::Footage(f))
+    }
+
+    fn path_of(s: &Session, id: ItemId) -> String {
+        match s.project.item(id).map(|i| &i.kind) {
+            Some(ItemKind::Footage(f)) => f.path.clone(),
+            _ => String::new(),
+        }
+    }
+
+    #[test]
+    fn relinking_one_file_finds_the_others_that_moved_with_it() {
+        let d = temp("one");
+        let new = d.join("moved");
+        std::fs::create_dir_all(new.join("shots")).unwrap();
+        std::fs::create_dir_all(new.join("audio")).unwrap();
+        for f in ["shots/a.mov", "shots/b.mov", "audio/m.wav"] {
+            std::fs::write(new.join(f), b"x").unwrap();
+        }
+        let mut s = Session::default();
+        let a = add(&mut s, "/gone/proj/shots/a.mov");
+        let b = add(&mut s, "/gone/proj/shots/b.mov");
+        let m = add(&mut s, "/gone/proj/audio/m.wav");
+        let other = add(&mut s, "/elsewhere/c.mov");
+        let target = new.join("shots/a.mov").to_string_lossy().to_string();
+        let r = s.execute("footage.relink", json!({"item": a.0, "path": target})).unwrap();
+        assert_eq!(r["relinked"], json!([a.0, b.0, m.0]), "{r}");
+        assert_eq!(r["stillMissing"], 1);
+        assert_eq!(path_of(&s, m), new.join("audio/m.wav").to_string_lossy());
+        assert_eq!(path_of(&s, other), "/elsewhere/c.mov");
+        // One undo step brings every path back.
+        s.execute("edit.undo", json!({})).unwrap();
+        assert_eq!(path_of(&s, b), "/gone/proj/shots/b.mov");
+        // Errors: no such file, not footage.
+        assert!(s.execute("footage.relink", json!({"item": a.0, "path": "/nope/a.mov"})).is_err());
+        assert!(s.execute("footage.relink", json!({"item": 999_999, "path": target})).is_err());
+        let _ = std::fs::remove_dir_all(d);
+    }
+}
diff --git a/crates/engine/src/footage_check.rs b/crates/engine/src/footage_check.rs
index f5db284e..1ff33a84 100644
--- a/crates/engine/src/footage_check.rs
+++ b/crates/engine/src/footage_check.rs
@@ -27,6 +27,8 @@ struct Job {
 enum Found {
     Missing(bool),
     Probed(Box<Footage>),
+    /// Found again under the project's new folder (the project was moved with its footage).
+    Moved(Box<Footage>),
 }
 
 fn exists(s: &dyn crate::Services, path: &str) -> bool {
@@ -52,6 +54,7 @@ pub fn start(s: &mut Session, items: Option<Vec<ItemId>>, wait: bool) -> crate::
     let services = s.services.clone();
     let importer = s.importer.clone();
     let rate = s.sequence_rate();
+    let project_dir = s.path.as_deref().and_then(crate::commands::relink_moved::project_dir);
     let n = jobs.len();
     s.spawn_task("footageCheck", format!("Checking footage ({n} items)"), wait, move |ctl| {
         let mut found: Vec<(ItemId, Found)> = Vec::with_capacity(jobs.len());
@@ -68,6 +71,14 @@ pub fn start(s: &mut Session, items: Option<Vec<ItemId>>, wait: bool) -> crate::
                 // placeholders, as in After Effects).
                 exists(services.as_ref(), &f.path) || f.sequence.iter().any(|p| exists(services.as_ref(), p))
             };
+            // Moved with the project: the same place under the project's folder.
+            if !present
+                && let Some(dir) = &project_dir
+                && let Some(nf) = crate::commands::relink_moved::find_moved(services.as_ref(), dir, f)
+            {
+                found.push((j.id, Found::Moved(Box::new(nf))));
+                continue;
+            }
             // Saved without metadata (a hand-written or converted project): probe it now.
             let needs_probe = present && f.width == 0 && f.height == 0 && f.kind != FootageKind::Audio;
             let probed = importer.as_ref().filter(|_| needs_probe).map(|imp| match f.kind {
@@ -105,7 +116,7 @@ pub fn start(s: &mut Session, items: Option<Vec<ItemId>>, wait: bool) -> crate::
 /// not an edit (the same as After Effects marking footage missing at open).
 fn apply(s: &mut Session, found: Vec<(ItemId, Found)>) -> Value {
     let checked = found.len();
-    let (mut missing, mut probed, mut changed) = (0, 0, false);
+    let (mut missing, mut probed, mut moved, mut changed) = (0, 0, 0, false);
     let p = std::sync::Arc::make_mut(&mut s.project);
     for (id, f) in found {
         let Some(ItemKind::Footage(cur)) = p.item_mut(id).map(|i| &mut i.kind) else { continue };
@@ -122,6 +133,11 @@ fn apply(s: &mut Session, found: Vec<(ItemId, Found)>) -> Value {
                 *cur = *nf;
                 changed = true;
             }
+            Found::Moved(nf) => {
+                moved += 1;
+                *cur = *nf;
+                changed = true;
+            }
         }
     }
     if changed {
@@ -133,10 +149,17 @@ fn apply(s: &mut Session, found: Vec<(ItemId, Found)>) -> Value {
         }
         s.events.push(crate::Event::PurgeCaches);
     }
-    if missing > 0 {
-        s.toast(format!("{missing} footage item(s) missing (File ▸ Dependencies ▸ Find Missing Footage)"));
+    if moved > 0 {
+        s.toast(format!("Found {moved} footage item(s) in the project's new folder"));
     }
-    json!({"checked": checked, "missing": missing, "probed": probed})
+    if missing > 0 {
+        s.toast(format!("{missing} footage item(s) missing (File ▸ Dependencies ▸ Relink Missing Footage in Folder…)"));
+    }
+    let mut out = json!({"checked": checked, "missing": missing, "probed": probed});
+    if moved > 0 {
+        out["relinked"] = json!(moved);
+    }
+    out
 }
 
 pub(crate) fn command(s: &mut Session, p: &Value) -> crate::Result<Value> {
@@ -217,6 +240,34 @@ mod tests {
         let _ = std::fs::remove_dir_all(dir);
     }
 
+    #[test]
+    fn footage_moved_with_its_project_is_found_on_open() {
+        let d = std::env::temp_dir().join(format!("ec-footage-moved-{}", std::process::id()));
+        let _ = std::fs::remove_dir_all(&d);
+        std::fs::create_dir_all(d.join("Job/shots")).unwrap();
+        std::fs::write(d.join("Job/shots/a.png"), b"x").unwrap();
+        // Saved on another machine: the footage sat next to the project in /Users/x/Job.
+        let mut s = session_with(&["/Users/x/Job/shots/a.png", "/Users/x/elsewhere/b.png"]);
+        let path = d.join("Job/p.ecproj");
+        s.execute("file.saveAs", json!({"path": path.to_string_lossy()})).unwrap();
+        let mut o = Session::default();
+        o.execute("file.open", json!({"path": path.to_string_lossy()})).unwrap();
+        let r = o.execute("footage.check", json!({"wait": true})).unwrap();
+        assert_eq!((r["relinked"].as_u64(), r["missing"].as_u64()), (Some(1), Some(1)), "{r}");
+        let paths: Vec<String> = o
+            .project
+            .items
+            .values()
+            .filter_map(|i| match &i.kind {
+                ItemKind::Footage(f) => Some(f.path.clone()),
+                _ => None,
+            })
+            .collect();
+        assert!(paths.contains(&d.join("Job/shots/a.png").to_string_lossy().to_string()), "{paths:?}");
+        assert!(!o.is_dirty(), "finding the files is not an edit");
+        let _ = std::fs::remove_dir_all(d);
+    }
+
     #[test]
     fn open_starts_the_check_when_asked() {
         let mut s = session_with(&["/nonexistent/ec/a.mov"]);
diff --git a/crates/host/tests/relink.rs b/crates/host/tests/relink.rs
new file mode 100644
index 00000000..5bb31b4e
--- /dev/null
+++ b/crates/host/tests/relink.rs
@@ -0,0 +1,56 @@
+//! Relinking footage that moved (docs/footage.md "Replacing and reloading"): Replace Footage on a
+//! missing item relinks the other missing items that moved with it, as in After Effects.
+
+use std::path::{Path, PathBuf};
+
+use effectcraft_engine::project::ItemKind;
+use serde_json::json;
+
+fn icon() -> Vec<u8> {
+    std::fs::read(Path::new(env!("CARGO_MANIFEST_DIR")).join("../../assets/app-icon/hicolor/16x16/apps/ai.storyteller.effectcraft.png")).unwrap()
+}
+
+fn footage_paths(s: &effectcraft_engine::Session) -> Vec<(u64, String, bool)> {
+    let mut v: Vec<(u64, String, bool)> = s
+        .project
+        .items
+        .values()
+        .filter_map(|i| match &i.kind {
+            ItemKind::Footage(f) => Some((i.id.0, f.path.clone(), f.missing)),
+            _ => None,
+        })
+        .collect();
+    v.sort();
+    v
+}
+
+#[test]
+fn replacing_a_missing_file_relinks_the_others_that_moved_with_it() {
+    let root: PathBuf = std::env::temp_dir().join(format!("ec-host-relink-{}", std::process::id()));
+    let _ = std::fs::remove_dir_all(&root);
+    let old = root.join("Job");
+    std::fs::create_dir_all(old.join("stills")).unwrap();
+    std::fs::write(old.join("stills/a.png"), icon()).unwrap();
+    std::fs::write(old.join("stills/b.png"), icon()).unwrap();
+    let mut s = effectcraft_host::session();
+    let paths: Vec<String> = ["stills/a.png", "stills/b.png"].iter().map(|p| old.join(p).to_string_lossy().to_string()).collect();
+    s.execute("file.import", json!({"paths": paths, "sequence": false})).unwrap();
+    let before = footage_paths(&s);
+    assert_eq!(before.len(), 2, "{before:?}");
+    // The job folder moves; both files go missing.
+    let new = root.join("Archive/Job");
+    std::fs::create_dir_all(root.join("Archive")).unwrap();
+    std::fs::rename(&old, &new).unwrap();
+    let r = s.execute("footage.check", json!({"wait": true})).unwrap();
+    assert_eq!(r["missing"], 2, "{r}");
+    // Locating one finds the other.
+    let a = before.iter().find(|(_, p, _)| p.ends_with("a.png")).unwrap().0;
+    let r = s.execute("file.replaceFootage", json!({"item": a, "path": new.join("stills/a.png").to_string_lossy()})).unwrap();
+    assert_eq!(r["relinked"].as_array().map(Vec::len), Some(1), "{r}");
+    let after = footage_paths(&s);
+    assert!(after.iter().all(|(_, p, missing)| p.starts_with(&*new.to_string_lossy()) && !missing), "{after:?}");
+    // One undo step puts both back.
+    s.execute("edit.undo", json!({})).unwrap();
+    assert_eq!(footage_paths(&s).iter().map(|(_, p, _)| p.clone()).collect::<Vec<_>>(), before.iter().map(|(_, p, _)| p.clone()).collect::<Vec<_>>());
+    let _ = std::fs::remove_dir_all(root);
+}
diff --git a/docs/footage.md b/docs/footage.md
index 458c4c99..20ca8926 100644
--- a/docs/footage.md
+++ b/docs/footage.md
@@ -98,6 +98,14 @@ vectors, positions and IDs are never the picture. EXtractoR reads every other la
 - **File ▸ Replace Footage ▸ File…** (Ctrl+H) points the item at another file. Pick a numbered
   file to replace it with that file's whole sequence (`file.replaceFootage {"path": …,
   "sequence": false}` for one frame).
+- **Relinking moved files.** `footage.relink {"item": id, "path": …}` points a missing item at
+  its file's new location, keeping its interpretation, and relinks every other missing item that
+  was in the same place relative to it (the whole folder moved, a drive was renamed, a project
+  made on Windows opened on macOS); File ▸ Replace Footage on a missing item does the same. One
+  undo step; `footage.missing` lists what is still missing.
+- **A project moved with its footage** finds it again on open: the footage check that runs after
+  File ▸ Open tries each missing file at the same place under the project's new folder, without
+  marking the project modified.
 - **File ▸ Reload Footage** (Ctrl+Alt+L) reads the files again. A sequence picks up frames
   added to its folder (a render still in progress) and keeps its interpretation.