Peter Scanavino

A second cast member who showed up as a villain before he turned into a good guy, Peter Scanavino's first turn on "Law & Order: SVU" was as Johnny Dubcek, a janitor who attacks a school's athletic coach because he claims he saw the coach assaulting a young girl. As it turns out, though, Johnny is a victim of sexual abuse himself, and he saw a situation that wasn't real due to his past trauma.

Ultimately, he goes to prison, and the man who assaulted him ends up in a cell nearby… which is a pretty bleak ending. Also, Mike Tyson is in this episode, for some reason.

That was in 2013; just one year later, Scanavino played brand-new detective Dominick Carisi Jr. on "Law & Order: SVU," a headstrong and relatively green member of the special victims unit who often needed different lifestyles and social norms explained to him (presumably so he could be an audience surrogate for those curious about issues like gender identity or women assaulting men).

Ultimately, in the show's 21st season, Carisi became an assistant district attorney, following in Casey Novak's confusing footsteps. It's weird enough that Scanavino played a villain just one year earlier, but the fact that he was so prominent in the episode is probably the strangest part.

Kelli Giddish

Kelli Giddish is the final main cast member on this list to play two characters on "Law & Order: SVU," but unlike Diane Neal and Peter Scanavino, she played a victim, not a villain. In the Season 8 episode "Outsider," SVU detective Fin Tutuola (Ice-T) investigates the rape of a young woman who knows his son and ends up working with Brooklyn-based detective Chester Lake (Adam Beach) to try and track down a serial rapist who's been attacking women throughout different boroughs.

The article is not finished. Click on the next page to continue.