A former schoolmate of Bruce Banner and low-ranking scientist within S.H.I.E.L.D.'s gamma radiation-research division, Philip Sterns developed a deranged love/obsession with Banner's "career" as the Hulk. Sterns subjected himself to a multitude of experiments involving gamma-radiation to emulate his "hero." This resulted in Sterns turning into a distorted monstrosity possessed of vast superhuman strength. Calling himself Madman, Sterns plotted to kill the Hulk, but he was defeated after a long battle and arrested by S.H.I.E.L.D.
He was ultimately freed by agents of HYDRA who recruited him into the Masters of Evil as one of their heavy-hitters.
Powers and Abilities
Powers
Like the Hulk, Madman has vast superhuman strength. Unlike the Hulk, Madman is unable to become stronger as he becomes angrier, but he is capable of creating significant boosts in his size, density and power, making him greatly exceed the Hulk's calm state for brief periods of time.