Because you like Daniel LaRusso in The Karate Kid

Whether it's a companion he’s failed or lingering guilt from the war, the Doctor can never truly let go of his past lives. See them in Doctor Who.

Frederick Frankenstein is an eccentric (O.K., maybe a little insane) professor who is excited to be delving into his family's past. See them in Young Frankenstein.

Squidward Tentacles is a pretentious clarinet player in search of peace and quiet. See them in SpongeBob SquarePants.

Rory Williams is a caring companion whose specialty is looking after others. See them in Doctor Who.

Serena van der Woodsen is a wild child. Too wild, her friends and family might argue. See them in Gossip Girl.

Zoe Benson may seem like a shy girl-next-door, but she has the inner fortitude of a powerful witch leader. See them in American Horror Story.

Bree Van De Kamp likes her whiskey's neat, her napkins pressed, and her guns loaded. See them in Desperate Housewives.

Breaking bones and hearts, Callie Torres has figured out how to put the bones back together. But the hearts? Not so much. See them in Grey's Anatomy.

They say prison changes you, and Piper Chapman is figuring that out the hard way. See them in Orange Is The New Black.

Catherine Linton was once spontaneous and rowdy but ever since marrying the wealthy Edgar, she has morphed into a boiling pot of emotional outbursts. See them in Wuthering Heights.

A compassionate medical student, Martha Jones has found a Doctor she can really look up to. See them in Doctor Who.