Because you like Donna Carmichael in Mamma Mia!

She's mostly doom and gloom, but you'd get nowhere without Sadness. See them in Inside Out.

Shaun is used to being lazy. And now, you're asking him to fight for his life? See them in Shaun of the Dead.

Dory is more than a little forgetful, but she'll always remember to have your back. See them in Finding Nemo.

It’s usually the good-looking, charismatic, play-by-their-own-rules types that get everyone into trouble, and Tyler Durden is Exhibit A. See them in Fight Club.

Willow Rosenberg may be a witch who can defeat the forces of evil, but she still gets emotional over kittens on the Internet. See them in Buffy the Vampire Slayer.

Aang is already a master airbender and once he learns to manipulate water, earth, and fire, he'll be truly unbeatable. See them in Avatar: The Last Airbender.

Daring on a bike but haunted in his personal life, even Johnny Blaze isn't fast enough to outride his past. See them in Ghost Rider.

In charge of stocking the office's supply of cigarettes and liquor, Joan Holloway could run the whole company if they would let her. See them in Mad Men.

Although Jareth seems like he's just a harmless romantic, his powers make him a formidable foe. See them in Labyrinth.

A suave womanizer, Jacob Palmer has turned seduction into a science. See them in Crazy, Stupid Love.

Sabriel is smart enough to understand the dangers that await her and brave enough to face them anyway. See them in Abhorsen Series.