Previously, on Mass Effect 3…
You're Commander Shepard, racing to build the Crucible superweapon and unite the galaxy against the Reapers. You just chased the last missing piece, the Catalyst, to Thessia, the asari homeworld, as it fell to the Reapers.
- WHERE: Thessia, burning under the Reaper invasion - QUEST: "Priority: Thessia", hunting the Catalyst clue hidden in a Prothean temple
RIGHT NOW: Recover from the loss. Cerberus's assassin Kai Leng stole the Catalyst information and escaped, leaving you a step behind the Illusive Man.