In the game, the player, or Agent, is a S.H.I.E.L.D. recruit just finishing his or her training when a mysterious Pulse comes out of space, showering New York with shards of Isotope-8: an unknown but versatile substance capable of boosting human strength, speed, and endurance. Naturally, the criminal underworld is eager to capitalize on this new source of power, but some of the bigger names in villainy are also getting in the game -- notably HYDRA, A.I.M., the Hand, the Maggia criminal syndicate, the Wrecking Crew... And there may well be a man-behind-the-man in the person of Magneto, the Mandarin, Dormammu, or even Doctor Doom responsible for getting all these baddies working together like never before.