As Captain America becomes more obsessed with bringing Baron Zemo to justice, the Masters of Evil escape their interdimensional exile. Plotting against Captain America, they bail out confessed embezzler Simon Williams to offer him a chance to get back at Tony Stark, whom Williams blames for his own downfall. Zemo bombards Williams with ionic rays, causing him to grow larger and stronger. Dubbed Wonder Man by Zemo, Williams agrees to join the Avengers to betray them from within. The Masters stage a payroll robbery, and after the Avengers arrive to fight them, Wonder Man steps in to “help” the heroes, causing the Masters to flee. Wonder Man asks to join the Avengers; when his story raises suspicions, the Enchantress casts a spell on the Avengers, persuading them that Wonder Man is dying from the effects of his ionic treatments. The Avengers diligently search for a cure to the hero’s affliction, but eventually Zemo has Wonder Man capture the Wasp and lures the male Avengers into Zemo’s clutches. Swiftly regretting betraying the Avengers, Wonder Man attacks the Masters of Evil himself, despite knowing that he will die without Zemo’s antidote, allowing Thor time to free himself. The Masters retreat as the Avengers rush to the dying Wonder Man’s side.