Infinity has arrived! he Avengers' main squad is light-years away in space, contending with the Builders! Thanos' marauders are ransacking the Earth, doing as they please! Who will defend mankind? The all-new Mighty Avengers! Luke Cage! The Superior Spider-Man! Spectrum! The White Tiger! The new Power Man! A mysterious figure in an ill-fitting Spider-Man Halloween costume! And more! These unlikely heroes must assemble when no one else can - against the unrelenting attack of Proxima Midnight! But that's easier said than done...and when Promixa begins killing New York City one block at a time, Cage's ad-hoc Avengers might not be able to stop her...and the one hero who can is at the bottom of the Mariana Trench! And then things get worse! Will the Mighty Avengers be destroyed before they even get started?