In this issue, Captain America and Iron Man respond to a threat from Mars with the core team of Avengers including Thor, Black Widow, Hulk and Hawkeye. The team discovers that a new villain Ex Nihilo and his crew are terraforming Mars and plans to wipe out humanity on Earth after finishing up on the red planet.
The team takes on these new guys but are soundly beaten. Nihilo send Captain America back to Earth while keeping the rest of the Avengers in Mars. When Captain America recovers he kicks start the reserve program for the Avengers that he and Tony Stark develop previously (in the early part of the issue). The call comes and the new Avengers response team is born.
