Meanwhile, Peter's finally made the needle on his Whatever Sensor drop all the way down to zero, so I guess his head won't blow off. He wipes his brow, and then senses something is wrong. He puts his hand on a rail near him, and then presumably feels a vibration because he turns (just as we see Fauxlivia racing towards him) and sees a train just metres away. He freezes up, so it's a good thing Fauxlivia was there to grab him and pull him into an alcove on the side.
Back at the platform, the homeless man's headless body is zipped up into a bodybag, with Walter explaining that he must have had some sort of surgical implant for such a "catastrophic explosion" like that. "Dental ceramic crowns. If they were to vibrate at just the right resonant frequency ... I always hated dentists."
Broyles is still stuck on wondering why there would even be pieces of the weapon over here, so Peter's all, "You got a better explanation? We're talking about two universes here. Two of each one of us." Well, not of you, Peter. Not anymore. "At this point, would anything really surprise you?" he concludes. "Bacon-flavoured pudding. That would surprise me," says Walter. God, be careful what you wish for, Walter. I tried some bacon-flavoured chapstick this summer, felt like I was smearing my lips with bacon grease. I just about threw up. I'm getting queasy just recalling it.
Anyway, Peter takes the device back to the lab to work on it some more, and he runs into Fauxlivia, who notes that it looks like he has other plans, and he's all "Do you mind?" and it's OK with Fauxlivia, given that she's got a corpse to clean up. Plus she's DVR'd the first few episodes of Boardwalk Empire and she really wants to give it a shot.
Then Broyles tells Walter that today was a bad day but it could have been a lot worse. "Your quick thinking saved a lot of lives, Dr. Bishop. Good work," he says, and pats Walter on the arm. Walter's got other things on his mind, though, and he pulls out the key from Bell, and stares at it.
And now we're in one of those cavernous banks in 150-year-old buildings because no one on television ever goes to a branch in a strip mall, and he gets out the safe-deposit box. He opens it, and then looks somewhat taken aback.
Meanwhile, Peter's working at the lab, examining the device.