After the events of the episode "Task Force X" (from "Justice League Unlimited"), the fire from that explosion is still left unintended as the other heroes investigate. However, unbeknownst to them, Plastique, somehow survive from the explosions earier, left clinically injured, with her clothes burned up as she crawls away from them without being noticed.

(Damn... Who knew my explosives would be turned on me. God, I should've just escaped with them when I have a chance...)

As she continues to crawl through the tower, she arrives to the room, filled with escape pods.

(I guess this must be my way out, huh? I need to retreat to go somewhere safe from them...)

As she climbs into one of the escape pods, then it proceeds to eject from the Watchtower and heading towards earth.