Synopsis
Captain Marvel enters Avengers Mansion with Moondragon to find Drax the Destroyer holding his own against Black Panther, Mantis, Swordsman and Vision. He stops the fray and lets Drax explain that the Titan computer ISAAC says Thanos has the Cosmic Cube. Vision calls in Captain America, Iron Man, Scarlet Witch and Thor to hear Drax's tale. CM also summarises the events of #25-30 (some of which involved the Avengers anyway).
On Titan Thanos overhears this via the Cube, as he gloats over his captive brother Eros and father Mentor. He decides that Drax, Iron Man, Mar-Vell and Moondragon, who know stuff about him, must die, leaving the Avengers impotent to stop him. He then reveals that his campaign of conquest and destruction is all for love of his constant companion, whom others can't see. We get the clearest hints yet that she is Death.
Thanos now teleports his 4 targets away from the Avengers to Titan, and traps them in bio-electric fields such as hold Eros and Mentor. Now he shows his captives how he will send his spacefleet against Earth, and then use that as a base to conquer the universe. And caps it by showing them Kronos, the incorporeal Titan creator/god, in chains.
Back on Earth Scarlet Witch breaks the news to Rick Jones' girlfriend Lou-Ann that his alter-ego Captain Marvel has been kidnapped by Thanos. Lou-Ann is still recovering at the Mansion after being a slave of the Controller. And on Titan CM strains to bring his wristbands together inside the containment field, and succeeds in swapping places with Rick in the Negative Zone. And the resulting surge of energy disrupts the field, freeing all the heroes.
Rick quickly reverts to Mar-Vell, and all but Mentor attack Thanos, trying unsuccessfully to prevent him from using the Cosmic Cube. Mentor instead mentally contacts ISAAC and gets the computer to switch off the 'cosmic gyro' which keeps the ruined moon in orbit around Saturn. And the small planet lurches off into space.
Mar-Vell's new Cosmic Awareness alerted him to what would happen, and he uses the moment of instability to kick the Cube out of Thanos' hand. Eros, Iron Man and Drax fail to stop the villain trying to reach the cosmic bauble. CM lasts longer, but even he is felled by the mad Titan. Thanos grabs the Cube as Moondragon wages Mind War against him. Until she collapses in defeat.
Thanos uses the Cube to bind his foes with chains of astral energy, and return Titan to its orbit. Then he uses it for the real purpose he wanted it. Sheathed in coruscating energy he disappears. The heroes are freed and the Cube falls at their feet.
But Thanos has not been destroyed. Instead his visage appears in space outside the planetoid. And he tells them he asked the Cube to transform him into a god, omniscient and omnipresent.