The Avengers journey into deep space, where they unite the intergalactice races against the Builders - deadly aliens who seek to destroy the known galaxy.

While the heroes are gone, Thanos sets his sight son Earth, sending back the Black Order to launch the assault.

It falls to the Inhumans, Black Panther, Doctor Stranger, the X-Men, and more to defend Attilian, Wakanda, Atlantis, and the rest of the planet. To defeat Thanos, the defending forces will need to employ a new weapon - one that may be as deadly as the invading force.