diff --git a/handle_imported_video.py b/handle_imported_video.py
index e31b402..08a03c3 100644
--- a/handle_imported_video.py
+++ b/handle_imported_video.py
@@ -78,7 +78,7 @@ if _ACTION == "join":
         if os.path.exists(_FULL_PATH + "100GOPRO"):
             _FULL_PATH = _FULL_PATH + "100GOPRO"
         for filename in os.listdir(_FULL_PATH):
-            if filename.endswith(".MP4"):
+            if filename.endswith(".MP4") and not filename.startswith("joined_"):
                 prefix = filename[0:2]
                 part = prefix + filename[2:4]
                 seq = filename[4:8]