In the Mark Millar and John Romita Jr. comic books, Dr. Gravity claims to be a physics professor who invented the "Gravity Pole," a device which can make something 20 times its actual weight. He actually is a college student majoring in English, who joins Kick-Ass (Aaron Johnson) in his adventures. The "Gravity Pole" is actually just a baseball bat covered in tinfoil.
Chloe Moretz, Christopher Mintz-Plasse, and Nicolas Cage are expected to reprise their roles from 2010's Kick-Ass, with John Leguizamo recently signing on to play Javier, Red Mist's new bodyguard.