After testifying at Controller’s trial at the Vault, Cap and Pym depart as Vault warden Truman Marsh resumes his work. Later, Marsh’s experiment on inmate Mentallo causes a power surge which enhances Mentallo’s telepathy, enabling him to contact and conspire with fellow inmate Venom. Mentallo forces a Guardsman to free Venom, who frees other inmates while battling security. Intercepting the alarm, Cap and Pym turn back and recapture fleeing inmates Orka, Griffi n and Bullet. Meanwhile, more Avengers and Freedom Force are en route. Venom takes Guardsmen hostage and tries to negotiate his way out in return for their lives, but Marsh refuses. The facility secretly contains a bomb the President can detonate to prevent mass escapes, but Marsh has rewired it to give himself control, and plans to use it. He sends Freedom Force into an access tunnel that might enable a surprise attack on the inmates, then discovers the breakout has already activated the bomb, with minutes to detonation. Before he can escape, Venom and Vermin capture him. The Avengers learn of the bomb and split up, trying to stop it and the inmates. Scouting ahead, Vision is captured by Klaw. Thunderball challenges Venom’s leadership, backed by Electro and Ironclad, but they are subdued by the Avengers while trying to escape. Freedom Force is captured and agrees to lead the Avengers into a trap to save themselves, but the Avengers foil the ambush. Meanwhile, Rhino and Armadillo try to stop Venom, wanting to serve their sentences, but Controller and Klaw defeat them. While the Avengers and Freedom Force clash over how to interrogate their prisoners, Venom and his followers arrive with a captured Iron Man and Pym, forcing their surrender. Pym tells the escapees about the bomb, and with Thunderball’s verification he’s allowed to go with Iron Man and Thunderball to disarm it, providing the other heroes remain imprisoned. The bomb is disarmed, and the grateful inmates want Thunderball to lead them now. While a jealous Venom attacks Thunderball, the Vision escapes, freeing the other heroes. Pym and Iron Man confi scate and modify Controller’s discs, amplifying and controlling Mentallo’s telepathy, subduing nearly all the inmates. Marsh, wanting vengeance for his parents dying in a super-battle, sets the Vault’s energy reactor to blow. Venom kills Marsh, Pym subdues Venom, and Iron Man teams with inmate Radioactive Man to absorb enough of the reactor’s atomic energy to shut it down safely.