diff --git a/api/src/models/entry/movie-entry.ts b/api/src/models/entry/movie-entry.ts
index d7ca4fc2..7e6e9e14 100644
--- a/api/src/models/entry/movie-entry.ts
+++ b/api/src/models/entry/movie-entry.ts
@@ -4,8 +4,8 @@ import { bubbleImages, madeInAbyss, registerExamples } from "../examples";
 import { Progress } from "../history";
 import {
 	DbMetadata,
-	ExternalId,
 	Image,
+	MovieEpisodeId,
 	Resource,
 	SeedImage,
 	TranslationRecord,
@@ -20,7 +20,7 @@ export const BaseMovieEntry = t.Composite(
 			order: t.Number({
 				description: "Absolute playback order. Can be mixed with episodes.",
 			}),
-			externalId: ExternalId(),
+			externalId: MovieEpisodeId,
 		}),
 		BaseEntry(),
 	],
diff --git a/api/src/models/utils/external-id.ts b/api/src/models/utils/external-id.ts
index 806c790d..39f6451e 100644
--- a/api/src/models/utils/external-id.ts
+++ b/api/src/models/utils/external-id.ts
@@ -30,6 +30,31 @@ export const EpisodeId = t.Record(
 );
 export type EpisodeId = typeof EpisodeId.static;
 
+export const MovieEpisodeId = t.Record(
+	t.String(),
+	t.Union([
+		t.Object({
+			dataId: t.String(),
+			link: t.Nullable(t.String({ format: "uri" })),
+		}),
+		t.Object({
+			serieId: t.String({
+				descrpition: comment`
+				Id on the external website.
+				We store the serie's id because episode id are rarely stable.
+			`,
+			}),
+			season: t.Nullable(
+				t.Integer({
+					description: "Null if the external website uses absolute numbering.",
+				}),
+			),
+			episode: t.Integer(),
+			link: t.Nullable(t.String({ format: "uri" })),
+		}),
+	]),
+);
+
 export const SeasonId = t.Record(
 	t.String(),
 	t.Object({