diff --git a/internal/services/reader.go b/internal/services/reader.go
index ad6dd62..efcbc16 100644
--- a/internal/services/reader.go
+++ b/internal/services/reader.go
@@ -105,9 +105,10 @@ func (s *ReaderService) DetectChapters(ctx context.Context, mediaItemID uuid.UUI
 
 	metadataBytes, err := json.Marshal(result)
 	if err == nil {
-		// Update media item with chapter metadata
-		// This would require a new query in database/queries.sql
-		_ = metadataBytes
+		_, _ = s.db.UpdateMediaItemChapterMetadata(ctx, database.UpdateMediaItemChapterMetadataParams{
+			ID:              pgtype.UUID{Bytes: mediaItemID, Valid: true},
+			ChapterMetadata: metadataBytes,
+		})
 	}
 
 	return chapters, nil