Simon Williams is the son of rich industrialist Sanford Williams, owner of Williams Innovations. Simon inherits the munitions factory after his father's death, but the company's profits fall due to its biggest competitor Tony Stark and his company Stark Industries. On the advice of his brother Eric, Simon tries to embezzle funds from his company but is caught and incarcerated. Simon blames Stark for this and accepts the proposition of master villain Baron Heinrich Zemo after the Enchantress pays his bail, as a pawn is required to infiltrate the Avengers. The desperate Simon Williams agrees and is transformed into an ion-powered being with superhuman powers. His powers are tested, and he is shown to have great superhuman strength and durability, even defeating the Executioner. Called Wonder Man by Zemo, he is then sent to meet and join the Avengers, with instructions to betray them at a critical moment so that Zemo's Masters of Evil can destroy the Avengers. Zemo ensures Wonder Man's loyalty by advising him that as a result of the treatment his body now requires periodic doses of a serum to survive—a serum that only Zemo can provide. The Avengers are lured into a trap and captured. The plan fails when Wonder Man decides to save the Avengers and aid them against Zemo, apparently at the cost of his own life.
