The Enchantress uses her magic to manipulate the Hulk into distrusting the rest of the Avengers and attacking Thor.

The Avengers discover the frozen body of Captain America and revive him, leading Baron Zemo to attack, seeking revenge against Cap for infecting him with Virus X.

Furious at Tony Stark for buying up his company, Simon Williams seeks revenge by undergoing a dangerous AIM procedure, overseen by MODOC and the Grim Reaper, Williams' brother, which turns him into a being of pure ion energy.

The Black Panther seeks the Avengers' aid in freeing his African nation of Wakanda from usurper king Man-Ape, and stopping Hydra agents Ulysses Klaw and the Grim Reaper from stealing Wakanda's supply of vibranium.

When the Leader creates a bubble of gamma radiation emanating from the Cube that mutates any human it touches, the Avengers team up with Doc Sampson to stop him. Meanwhile, Hawkeye infiltrates a Hydra base in order to capture Black Widow.

It's up to Hawkeye, the Hulk, and Thor to save the day when the Leader's gamma radiation ray mutates the rest of the Avengers and threatens to do the same to every human on earth.