diff --git a/python/tasks/tiktok/utils.py b/python/tasks/tiktok/utils.py
index aecbee0..e5f6e89 100644
--- a/python/tasks/tiktok/utils.py
+++ b/python/tasks/tiktok/utils.py
@@ -1,4 +1,5 @@
 import celery.app.task
+import os
 import asyncio
 import inspect
 import importlib
@@ -141,11 +142,13 @@ def grid_of_videos(paths: Iterable[str]) -> Any:
 
     grid = GridspecLayout(1, len(paths))
 
-    for i, filepath in enumerate(paths):
+    for i, path in enumerate(paths):
+        assert os.path.exists(path)
+
         out = Output()
         with out:
             display.display(display.Video(
-                url='/files/%s' % filepath,
+                url='/files/%s' % path,
                 #embed=True
             ))