On what TV series did the actor who played Ryan O'Reily on Oz play John Gavin?
Johnny Gavin (Rescue Me): Johnny Gavin is a fictional character on the FX drama series "Rescue Me". Dean Winters:  He is known for his role as Ryan O'Reily on the HBO prison drama "Oz", and has also appeared on such television series as "Rescue Me", "30 Rock", and "", as well as the character "Mayhem" in a series of Allstate Insurance commercials.
i don't know