Michael finds his soul self transported to Mallory, where he is forced to play for his soul against the mysterious Prophet. Meanwhile, Alex and Gates join forces to prevent the meltdown of Vega's nuclear reactor, and David tries to convince William to leave the city before it's too late.

After the Amphora is destroyed, Alex rallies the remaining survivors to defend the walls of Vega against the invading eight-balls. Meanwhile, Michael battles Gabriel while David tries to activate the wall cannons. In the past, the events leading up to the Apocalypse War are revealed.