diff --git a/docs/assets/site.css b/docs/assets/site.css
index 44ba0b6..ac492b6 100644
--- a/docs/assets/site.css
+++ b/docs/assets/site.css
@@ -407,6 +407,16 @@ code {
 /* Overview                                                            */
 /* ------------------------------------------------------------------ */
 
+/* Walkthrough video on the overview page */
+.video { margin: 0; }
+.video video {
+  display: block;
+  width: 100%;
+  height: auto;
+  border-radius: 3px;
+  background: var(--code);
+}
+
 .looks {
   margin-top: 48px;
   display: flex;
diff --git a/docs/index.html b/docs/index.html
index a47dc79..08c86da 100644
--- a/docs/index.html
+++ b/docs/index.html
@@ -22,7 +22,7 @@
 <div class="layout">
 <aside class="sidebar" id="sidebar">
   <a class="sidebar__logo" href="index.html" aria-label="layeris overview"><img src="assets/logo.svg" alt="" width="68" height="59"></a>
-  <nav class="sidenav" aria-label="Docs"><div class="sidenav__group"><a class="sidenav__page" href="index.html" aria-current="page">Overview</a><div class="sidenav__sections"><a href="#install">Install</a><a href="#quick-start">Quick start</a><a href="#load-and-save">Load and save</a><a href="#performance">Performance</a><a href="#contents">In these docs</a></div></div><div class="sidenav__group"><a class="sidenav__page" href="examples.html">Examples</a></div><div class="sidenav__group"><a class="sidenav__page" href="blend-modes.html">Blend modes</a></div><div class="sidenav__group"><a class="sidenav__page" href="operations.html">Operations</a></div><div class="sidenav__group"><a class="sidenav__page" href="api.html">API reference</a></div></nav>
+  <nav class="sidenav" aria-label="Docs"><div class="sidenav__group"><a class="sidenav__page" href="index.html" aria-current="page">Overview</a><div class="sidenav__sections"><a href="#video">Video</a><a href="#install">Install</a><a href="#quick-start">Quick start</a><a href="#load-and-save">Load and save</a><a href="#performance">Performance</a><a href="#contents">In these docs</a></div></div><div class="sidenav__group"><a class="sidenav__page" href="examples.html">Examples</a></div><div class="sidenav__group"><a class="sidenav__page" href="blend-modes.html">Blend modes</a></div><div class="sidenav__group"><a class="sidenav__page" href="operations.html">Operations</a></div><div class="sidenav__group"><a class="sidenav__page" href="api.html">API reference</a></div></nav>
   <div class="sidebar__foot">
     <a class="gh-link" href="https://github.com/subwaymatch/layer-is-python"><svg viewBox="0 0 16 16" width="15" height="15" fill="currentColor" aria-hidden="true"><path d="M8 0c4.42 0 8 3.58 8 8a8.013 8.013 0 0 1-5.45 7.59c-.4.08-.55-.17-.55-.38 0-.27.01-1.13.01-2.2 0-.75-.25-1.23-.54-1.48 1.78-.2 3.65-.88 3.65-3.95 0-.88-.31-1.59-.82-2.15.08-.2.36-1.02-.08-2.12 0 0-.67-.22-2.2.82-.64-.18-1.32-.27-2-.27-.68 0-1.36.09-2 .27-1.53-1.03-2.2-.82-2.2-.82-.44 1.1-.16 1.92-.08 2.12-.51.56-.82 1.28-.82 2.15 0 3.06 1.86 3.75 3.64 3.95-.23.2-.44.55-.51 1.07-.46.21-1.61.55-2.33-.66-.15-.24-.6-.83-1.23-.82-.67.01-.27.38.01.53.34.19.73.9.82 1.13.16.45.68 1.31 2.69.94 0 .67.01 1.3.01 1.49 0 .21-.15.45-.55.38A7.995 7.995 0 0 1 0 8c0-4.42 3.58-8 8-8Z"/></svg><span>GitHub</span></a>
     <div class="sidebar__meta"><button class="icon-button theme-toggle" type="button" data-theme-toggle aria-label="Switch to dark theme" title="Switch to dark theme"><svg class="icon-moon" viewBox="0 0 20 20" width="17" height="17" fill="none" stroke="currentColor" stroke-width="1.5" stroke-linejoin="round" aria-hidden="true"><path d="M16.2 12.4A6.6 6.6 0 0 1 7.6 3.8a6.6 6.6 0 1 0 8.6 8.6Z"/></svg><svg class="icon-sun" viewBox="0 0 20 20" width="17" height="17" fill="none" stroke="currentColor" stroke-width="1.5" stroke-linecap="round" aria-hidden="true"><circle cx="10" cy="10" r="3.3"/><path d="M10 2.6v1.7M10 15.7v1.7M2.6 10h1.7M15.7 10h1.7M4.8 4.8L6 6M14 14l1.2 1.2M4.8 15.2L6 14M14 6l1.2-1.2"/></svg></button><span class="version">v0.4.0</span></div>
@@ -57,6 +57,19 @@ <h1 class="wordmark">layeris</h1>
   <div class="looks__stage"><img data-look="original" hidden src="examples/originals/gamcheon-village.jpg" alt="Pastel houses on a hillside in Gamcheon Culture Village, Busan (Original)" width="960" height="640"><img data-look="cross-process" src="examples/cross-process.jpg" alt="Pastel houses on a hillside in Gamcheon Culture Village, Busan (Cross-processed)" width="960" height="640"><img data-look="pastel-dream" hidden src="examples/pastel-dream.jpg" alt="Pastel houses on a hillside in Gamcheon Culture Village, Busan (Pastel dream)" width="960" height="640"><img data-look="channel-swap" hidden src="examples/channel-swap.jpg" alt="Pastel houses on a hillside in Gamcheon Culture Village, Busan (Channel swap)" width="960" height="640"></div>
 </div>
 
+<section class="section" id="video">
+  <h2>Video</h2>
+  <p class="section__intro">A short walkthrough: installing, chaining operations, the blend
+    modes, curves and a few looks. Every edit in it is rendered by layeris.</p>
+  <figure class="video">
+    <video controls playsinline preload="metadata" width="1920" height="1080"
+        poster="video/poster.jpg">
+      <source src="video/layeris.mp4" type="video/mp4">
+      <a href="video/layeris.mp4">Download the video</a> (MP4).
+    </video>
+  </figure>
+</section>
+
 <section class="section section--roomy" id="install">
   <h2>Install</h2>
   <div class="cols">
diff --git a/video/out/layeris.mp4 b/docs/video/layeris.mp4
similarity index 100%
rename from video/out/layeris.mp4
rename to docs/video/layeris.mp4
diff --git a/docs/video/poster.jpg b/docs/video/poster.jpg
new file mode 100644
index 0000000..3126eb6
Binary files /dev/null and b/docs/video/poster.jpg differ
diff --git a/scripts/build_docs.py b/scripts/build_docs.py
index 6b86572..83f052d 100644
--- a/scripts/build_docs.py
+++ b/scripts/build_docs.py
@@ -82,6 +82,11 @@
 
 image.multiply(gradient)  # white is neutral for multiply"""
 
+# The walkthrough video on the overview page, rendered by the Remotion project
+# in video/ (`npm run render` and `npm run poster` write these files).
+VIDEO_SRC = "video/layeris.mp4"
+VIDEO_POSTER = "video/poster.jpg"
+
 # Thumbnails beside each page in the overview's "In these docs" list.
 CONTENTS_EXAMPLES = ["teal-and-orange", "double-exposure", "cyanotype"]
 CONTENTS_BLEND_MODES = [
@@ -406,6 +411,19 @@ def thumbs(paths: list[str]) -> str:
   <div class="looks__stage">{stage}</div>
 </div>
 
+<section class="section" id="video">
+  <h2>Video</h2>
+  <p class="section__intro">A short walkthrough: installing, chaining operations, the blend
+    modes, curves and a few looks. Every edit in it is rendered by layeris.</p>
+  <figure class="video">
+    <video controls playsinline preload="metadata" width="1920" height="1080"
+        poster="{VIDEO_POSTER}">
+      <source src="{VIDEO_SRC}" type="video/mp4">
+      <a href="{VIDEO_SRC}">Download the video</a> (MP4).
+    </video>
+  </figure>
+</section>
+
 <section class="section section--roomy" id="install">
   <h2>Install</h2>
   <div class="cols">
@@ -477,7 +495,7 @@ def thumbs(paths: list[str]) -> str:
         body=body,
         version=__version__,
         sections=[
-            ("install", "Install", 1), ("quick-start", "Quick start", 1),
+            ("video", "Video", 1), ("install", "Install", 1), ("quick-start", "Quick start", 1),
             ("load-and-save", "Load and save", 1), ("performance", "Performance", 1),
             ("contents", "In these docs", 1),
         ],
diff --git a/video/.gitignore b/video/.gitignore
index c2658d7..72aae85 100644
--- a/video/.gitignore
+++ b/video/.gitignore
@@ -1 +1,2 @@
 node_modules/
+out/
diff --git a/video/README.md b/video/README.md
index 60b8ab6..e21aa83 100644
--- a/video/README.md
+++ b/video/README.md
@@ -2,7 +2,9 @@
 
 A short walkthrough of layeris (1920×1080, 30 fps, 52.1 seconds),
 built with [Remotion](https://www.remotion.dev/). The rendered file is
-[`out/layeris.mp4`](out/layeris.mp4).
+[`docs/video/layeris.mp4`](../docs/video/layeris.mp4), where the docs site's
+overview page plays it, with
+[`docs/video/poster.jpg`](../docs/video/poster.jpg) as its poster frame.
 
 It follows the docs site's look: white page, DM Mono for the wordmark and
 code, Schibsted Grotesk for text, Besley for section titles, and the same
@@ -44,7 +46,8 @@ cd video
 npm install
 
 npm run start     # open Remotion Studio to preview and scrub
-npm run render    # render out/layeris.mp4
+npm run render    # render ../docs/video/layeris.mp4
+npm run poster    # render the poster frame, ../docs/video/poster.jpg
 ```
 
 To change an edit, update `scripts/build_assets.py` and rebuild the renders:
diff --git a/video/package.json b/video/package.json
index 67d2e39..2c8ce93 100644
--- a/video/package.json
+++ b/video/package.json
@@ -6,9 +6,10 @@
   "scripts": {
     "assets": "python3 scripts/build_assets.py",
     "start": "remotion studio",
-    "render": "remotion render LayerisVideo out/layeris.mp4",
+    "render": "remotion render LayerisVideo ../docs/video/layeris.mp4",
     "still": "remotion still LayerisVideo out/still.png",
-    "typecheck": "tsc --noEmit"
+    "typecheck": "tsc --noEmit",
+    "poster": "remotion still LayerisVideo ../docs/video/poster.jpg --frame=120 --image-format=jpeg --jpeg-quality=85"
   },
   "dependencies": {
     "@fontsource/besley": "5.2.8",