Our Boy Is Back (S01E03)

Rush confronts an old case that Vera was unable to solve involving a serial rapist who preys on single women. When the rapist sends a letter to the detective squad announcing he's returned to Philadelphia after a five-year absence and plans to strike again, Rush and Vera attempt to catch the criminal before he acts. The prime suspect in the past was Bruce Eldridge (Greg Zola), the boyfriend of a victim strangled to death during her attack. The detectives pursue Eldridge's possible involvement with the crimes; however, DNA evidence exonerates him. Rush's best hope of catching the rapist comes from the one victim, Ellen (Bree Turner), who caught a glimpse of her attacker and is able to provide Rush with a composite sketch. (Warner Bros. UK)