Watch Dogs hasn't launched yet, but it's launch trailer has, and if that makes no sense to you then just let all of the explosions knock the logic out from your skull. Who needs logic when everything is blowing up. No-one that's who! Just watch the explosions ya dingus.
Actually, I might exaggerating with the explosions. A lot of other stuff happens: driving, shooting people in the face, fancy hacking stuff and — of course — Aidan walking in slow motion from an explosion and totally not looking back at it. He knows the explosion has happened, he's the man that made the thing explode. It's all part of his masterplan idiots. Why would he bother looking back?
He's a cool dude that Aidan.