Ep 17. Teen Out of Time

Archie's time-traveling enemy once again menaces Riverdale with a monster from prehistoric times while Archie is trapped in Riverdale's past. Using the unreliable time belt, Archie manages to jump backward in time, visiting key points in Riverdale history. Each time Archie uses the time belt, he gets closer and closer to the present - but will he get back in time to save his friends from becoming dinosaur chow?