As the US Government create a force, known as Ultron, The Avengers are told they are not needed any longer. But when Ultron turns against Humanity, it's time for The Avengers to assemble yet again for their most dangerous challenge ever.

When an unexpected enemy emerges and threatens global safety and security, Nick Fury, director of the international peacekeeping agency known as S.H.I.E.L.D., finds himself in need of a team to pull the world back from the brink of disaster. Spanning the globe, a daring recruitment effort begins!

When the renegade crew of Serenity agrees to hide a fugitive on their ship, they find themselves in an action-packed battle between the relentless military might of a totalitarian regime who will destroy anything - or anyone - to get the girl back and the bloodthirsty creatures who roam the uncharted areas of space. But, the greatest danger of all may be on their ship.