Our heroes make it down thirteen floors and out the doors by the time their not-running pursuers have even found the room with the anti-matter. They stand there staring at it, with the Observer going in for a closer look, trying to figure out what it is. Then his eyes widen and his mouth gapes open.
Outside, the insurgents arrive in a plaza with the Massive Dynamic building behind them and Walter says he knows where the rest of his team is. "I know where we were ambered," he says and then with a loud buzzing and bright flashing, the building zaps out of existence. The other agents are astonished, but Walter barely blinks. "We should hurry. It's not far from here," he says. He walks off, with Etta and Simon left to look back at where Massive Dynamic used to be and likely think to themselves that they're lucky Walter's on their side.
And now we're in -- an antique typewriter shop? Well, I'll be. Etta's looking at the wall of amber in front of her, a man (looks like Peter) and a woman (harder to tell, which makes it suspicious) on opposite sides of the hole that was the slice of amber that contained Walter. Simon strolls up and wants to know what was up with her little moment with Walter back at Massive Dynamic. "You see him. He's half a fruitcake short of Christmas," she says. Simon doesn't seem particularly convinced, but Etta's no more forthcoming than that. She says the wand must be just about powered up and she walks off to get it.
Back at the Federal Building, Broyles is incredulous at a report from the agent at the transit station telling him it was Agent Foster with a woman and a man Foster said was her grandfather, but with a prisoner transport ID. "You may all play fast and loose up there in Boston, but here rules and regulations matter. If you prefer, I can certainly take this up with downtown," he says. God, shut up. When I am king, you will be first against the wall, arsehole.
Broyles assures him he can handle his agents and then goes out on to the floor to tell the seemingly only other agent out there to activate Foster's tracker (you'd think that, in an occupation, that such a device would just be on all the time) and to assemble a team. The Avengers? Probably not. Probably don't have the Avengers in this bullshit dystopian timeline.
Back at the Amber Typewriter Shop, Walter is examining, with some admiration, Foster's "augmentation buffers." Foster starts rambling about how Walter is just what they're looking for, someone to show people that they don't have to just accept their fate, that they can fight back and Walter gruffly cuts him off and suggests that with a little more focus and a little less pontificating, they might have the job done by now. OK, so this is a universe where Walter is against pontificating and in favor of complete, laser focus. And hamburgers bite people!