Plot summary
Alison purchases a nanny cam and finds that Donnie snuck out during the middle of the night. Paranoid, Alison ties him up, while also handling a neighborhood house party. Sarah impersonates Alison to question Donnie, who says he was covering up letters from a girl he dated when he and Alison were broken up. Paul follows Sarah and ultimately learns of their nature as clones. He also helps Sarah get rid of Vic when he continues to be a nuisance to her. Felix suspects Alison's neighbor, Aynsley Norris, of being the actual monitor. Meanwhile, Cosima is approached by Delphine Cormier, a fellow student. Cosima suspects Delphine of being her monitor, but goes with her to a lecture given by Dr. Aldous Leekie of the Dyad Institute, a proponent of "neolution" (using technology to advance human evolution ). Later, it is revealed that Delphine and Leekie are lovers.
Credits
Adapted from Wikipedia contributors, List of Orphan Black episodes. HTML formatting and reference markers removed.