This story follows from IRON MAN (1998) #7
The Lunatic Legion – an extremist Kree military group -- have declared war on Earth – and specifically the Avengers. They mistakenly blame them for detonating the bomb that destroyed their homeworld. Their first battle was against Iron Man and Warbird. They were unable to stop the Legion from acquiring an experimental power source that would further their plans. Warbird abandoned Iron Man to pursue the Lunatic Legion while they were escaping, leaving him to evacuate civilians.
In Brooklyn, Captain America stops two criminals trying to loot the headquarters of Congressional Candidate Andrew Bolt and then burn it to the ground. Bolt received the Skrull imposters support only to have his campaign abruptly halted when the truth was revealed. Cap delays them just long enough until the fire department arrives and extinguishes the fire.
Bolt arrives on the scene and is met by Cap. He explains that he will be unable to continue his campaign due to the actions of the Skrull impersonator. Cap then apologizes for his doppleganger ruining Bolt's career.
His conversation is interrupted when Warbird contacts him over Avengers' Identicard. She is being attacked by the Lunatic Legion in an abandoned missle silo near Cape Canaveral. As he leaves, he encourages Bolt to stay in the race.
Moments after she ends her transmission, Warbird is rendered unconscious by the Lunatic Legion. They decide that she would be of use in their experiments on human exposure to the Inhumans' Terrigen Mists. They hope that her Kree/human genetic structure will enable them to transform humanity into a race of slaves.
Warbird awakens during another experiment but is unable to stop the process or free herself. At this point Cap burts through the door and frees everyone. He was able to pinpoint her location through the Identicard. Once everyone has been evacuated from the room, Warbird updates Cap on the situation. She also admits that she has not contacted the other Avengers, much to Cap's dismay. The Kree have jammed all outgoing signals, preventing them from calling in reinforcements. With little choice Cap and Warbird begin to fight their way out of the compound.
In Los Angeles, General Ulysses Chapman unexpectedly divulges the complete mission parameters to remove a dictator in Moldavia during a live interview. The Pentagon is unable to abort the mission in time.
Cape Canaveral: While fighting their way out of the Kree compound, Cap's shield is heavily damaged by Legion member Byon Char. One punch from Char sends Cap flying into a separate building where the bodies of the dead test subjects are stored. He is horrified at this discovery and is reminded of the mass graves he saw during World War II. When Char comes in to finish him, he finds an angry Captain America waiting for him.
He quickly defeats him and rejoins Warbird, who points out that the Legion are preparing to leave. Cap tells her to let them and help evacuate everyone else. When she protests, Cap tells her that her behavior is unacceptable. She didn't call in the other Avengers because she was trying to prove herself to him. She's not fit for duty as an Avenger if she refuses to work with her teammates; her power fluctuations (which she believes to be the reason he disapproves of her) is irrelevant.
Despite his honest assessment (and subsequent protests), Warbird still pursues the Legion leaving Cap to evacuate the civilians. She is quickly captured by the Lunatic Legion – as was their plan all along. They decide to begin experimenting on her back at their moon base.
Continued in QUICKSILVER #10.