Watch The Strain Season 4 Episode 1 Online. Best and Free Online streaming for The Strain TV Show. We picked the best sites to stream s04e01. 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 The Strain Season 4 Episode 1 s04e01 at the top of the list.