diff --git a/yt_dlp/extractor/nrk.py b/yt_dlp/extractor/nrk.py
index 0f72561f98..ec69a94356 100644
--- a/yt_dlp/extractor/nrk.py
+++ b/yt_dlp/extractor/nrk.py
@@ -221,7 +221,7 @@ class NRKIE(NRKBaseIE):
                 'url': sub_url,
             })
 
-        chapters = None
+        chapters = []
         if data.get('skipDialogInfo'):
             chapters = [item for item in [{
                     'start_time': float_or_none(traverse_obj(data, ('skipDialogInfo', 'startIntroInSeconds'))),