The line between being a hero or a villain isn't as clear as Matt thought.
After surviving the fight at the factory, Matt's finally started to accept his Ability-and what it means to use it in the real world.
But then Ash arrives.
She has an Ability too. And unlike Matt, she's not interested in playing by the rules written by "normal" people. She makes Matt realize that as much as he wants to be, he'll never be normal.
So when Ash wants Matt to help her pull off a dangerous theft, what scares him the most is how much he understands her motives.
Matt has to make a choice. Joining Ash would mean crossing a line he may never come back from; but stopping her would mean fighting someone with an Ability like his own.
This time, Matt isn't just risking his life.
He's risking his soul.