Watch NCIS Season 15 Episode 23 Online. Best and Free Online streaming for NCIS TV Show. We picked the best sites to stream s15e23. Simply pick a site below and click "Watch Now!" button next to it. Some of the links may be broken, please upvote the working and good links so other users see those links for NCIS Season 15 Episode 23 s15e23 at the top of the list.