Synopsis
Maria Hill has gathered together the Avengers (and some others) who aren't directly involved with the case (despite Captain America's decision in #2 not to involve them) to tell them that there's a cosmic-level threat. Thanos has stolen an item of power, but she won't tell them what it is. But then the away team contacts them and Iron Man lets slip that it's a Cosmic Cube. (The Avengers are surprised to see Hulk alongside Cap, IM, Black Widow, Hawkeye and Thor.) The on-Earth Avengers are to prepare to defend the planet while the away team goes after Thanos.
Thanos is on Moord the homeworld of the Brotherhood of Badoon. He makes the usual promise of power over their enemies. All they have to do is hold off the approaching Avengers while he masters the Cube.
The Avengers are on their way in a souped-up quinjet, alongside the Guardians of the Galaxy in their own ship and Thor under his own steam. Iron Man waxes lyrical about the joys of being in space. Groot is now with the other Guardians (Bug, Drax, Gamora, Rocket Raccoon and Star-Lord). Suddenly they're attacked by a Badoon warship.
Iron Man and Thor bust into the Badoon ship, followed by the Guardians (except Groot). Mayhem ensues. The Badoon have a Monster of Badoon with them, but Drax just uses it as a club. Strangely, armoured Tony Stark also appears to be still back in the quinjet, until the 'Iron Man' fighting the Badoon proves to be Hulk who bursts out of the armour.
The surprise turns the tide as the other Avengers join the fray. But during the melee a Badoon accidentally ejects everyone into space.
And Thanos takes control of the Cube.