diff --git a/killstream/kill_trans_library.py b/killstream/kill_trans_library.py
index 707cf53..6ba4aa6 100644
--- a/killstream/kill_trans_library.py
+++ b/killstream/kill_trans_library.py
@@ -42,6 +42,9 @@ plex = PlexServer(PLEX_URL, PLEX_TOKEN, session=sess)
 if __name__ == '__main__':
 
     lib_id = sys.argv[1]
+    if lib_id not in TARGET_LIBRARIES:
+        print('Library accessed is allowed.')
+        exit()
     session_key = int(sys.argv[2])
 
     for session in plex.sessions():