diff --git a/calliope-web/package-lock.json b/calliope-web/package-lock.json
index 7d763dcd..f2f3602a 100644
--- a/calliope-web/package-lock.json
+++ b/calliope-web/package-lock.json
@@ -1,12 +1,12 @@
 {
 	"name": "calliope-web",
-	"version": "1.5.1",
+	"version": "1.5.2",
 	"lockfileVersion": 3,
 	"requires": true,
 	"packages": {
 		"": {
 			"name": "calliope-web",
-			"version": "1.5.1",
+			"version": "1.5.2",
 			"dependencies": {
 				"@tanstack/svelte-query": "^5.66.0",
 				"@types/three": "0.185.0",
diff --git a/calliope-web/package.json b/calliope-web/package.json
index 0e21ea13..ae150464 100644
--- a/calliope-web/package.json
+++ b/calliope-web/package.json
@@ -1,6 +1,6 @@
 {
 	"name": "calliope-web",
-	"version": "1.5.1",
+	"version": "1.5.2",
 	"private": true,
 	"scripts": {
 		"dev": "vite dev",
diff --git a/docs/changelogs/2026-09-16-bilingual-ui.md b/docs/changelogs/2026-09-16-bilingual-ui.md
new file mode 100644
index 00000000..16d6d186
--- /dev/null
+++ b/docs/changelogs/2026-09-16-bilingual-ui.md
@@ -0,0 +1,35 @@
+# Calliope 1.5.2 — bilingual UI (English / 中文) and one-command local start
+
+Every user-facing string used to be hardcoded English, spread across ~60
+components — so a Chinese-speaking user saw an English UI no matter how the app
+was configured, and there was no single place to change a label. This release
+routes the whole interface through a dictionary layer with a language switcher
+in the header.
+
+## What changed
+
+- **Full en/zh dictionary** — 1001 keys, mirrored 1:1 between `en.ts` and
+  `zh.ts`. Both are typed against `Dict` (`typeof en`), so the compiler rejects
+  a translation that is missing a key.
+- **Every component wired through `t()`** — nav rail, canvas, projects, story,
+  assets, script, queue, the video workspace, Build Scene, settings, agent chat,
+  toasts, and the error paths. No hardcoded English copy remains in the UI.
+- **Language switcher in the header** — English / 中文. The choice is stored in
+  `localStorage` (`calliope-lang`) and applied on reload; a missing or
+  unrecognized value falls back to English.
+- **Placeholder interpolation** — `t('key', { name: … })` substitutes `{name}`,
+  with a `count` shorthand that also fills `{n}`, the convention most
+  count-bearing strings use.
+- **Genre / tone / duration options** moved into `formOptions.ts`, mapping the
+  English values the backend stores onto dictionary keys — so stored project
+  data keeps working regardless of the display language.
+- **Local start/stop scripts** — `setup.bat` (idempotent first-time install),
+  `start.bat` (two visible windows), `start-bg.bat` (background, output to
+  `logs/`), and `stop.bat`.
+
+## Upgrade
+
+No migration and no new dependencies. `git pull`, then reload the frontend — an
+`npm install` in `calliope-web/` is only needed if you are coming from an older
+release. The UI defaults to English; switch to 中文 with the dropdown in the
+header.
diff --git a/docs/changelogs/README.md b/docs/changelogs/README.md
index 2efc71b1..31b73012 100644
--- a/docs/changelogs/README.md
+++ b/docs/changelogs/README.md
@@ -2,6 +2,7 @@
 
 Dated notes for GitHub releases. Newest first.
 
+- [2026-09-16 bilingual UI](./2026-09-16-bilingual-ui.md) — en/zh dictionary across every component; header language switcher; local start scripts (1.5.2)
 - [2026-09-13 clip shot brief](./2026-09-13-clip-shot-brief.md) — per-clip brief in the Video composer; two-column Video stage (1.5.1)
 - [2026-09-10 Build Scene + scene → clips](./2026-09-10-build-scene-clips.md) — 3D blockout composer; vision/doc input; 1 scene : N shot clips; faithful scripts (1.5.0)
 - [2026-09-07 chunking + cards](./2026-09-07-chunking-cards.md) — Story/script generate in chunks; ask_user cards appear (1.4.1)