This is a competition for the little guys: In one corner, E.T. (of E.T.), an adorable little extraterrestrial, who bonds with a human boy while trying to phone home.
Just as adorable, though far more deadly, is Abby in Let Me In (played by Chloë Grace Moretz), a young vamp who strikes up an unlikely friendship with a human boy.
Vampires, serial killers and aliens galore: Check out Hollywood's Top Monsters!