And just as everyone watching is thinking, "Since they have two generators, they'll need a synchroscope to make sure they're in perfect phase, duh," Peter points out that since they have two generators, they'll need a synchroscope as well to make sure they're in perfect phase. Walter says he knows that and so he would have thought of that, so he's likely got one in the amber by the fish tank.
Dontember explains Michael will traverse the wormhole to 2167, meet the Norwegian scientist and voila! -- change the course of human evolution. Astrid asks how he'll know who the scientist is and Dontember and Walter look awkward. Dontember then evasively says there'll be someone there to guide him. No one really looks askance at the two of them being cagey about the details, because it's not like they're doing anything complicated like time traveling or anything, and then Olivia's phone/comms thing rings. It's Broyles, who tells her he's on his way to Boston. Unbeknownst to him, he's being monitored and tracked, but he soon notices the gloves on his dashboard -- and then the Loyalist vehicle behind him in traffic. So he tells Olivia they're following him and he's going to lead them around as long as he can, but it's only a matter of time before they realize he's messing with them. "If I'm caught, they'll read me. I can protect my thoughts, but there's only so long that'll last," he says.
Olivia has the GENIUS idea that they'll come and get him instead. Yeah, HE'S BEING WATCHED, Olivia. Broyles isn't having that, obviously, and despite Olivia's objections, he hangs up, telling her to just get it done. Everyone looks glum and it's Walter who reminds them that Philip's right -- they've got to gather everything that's required and leave.
Peter's working his way through the amber looking for the synchroscope and finding everything but: He finds a syringe -- Walter, clearly lying, says he doesn't know what it's for -- and then another VHS tape, one that's addressed to him in Walter's handwriting. He puts it in, Walter watching too with a look of impending doom.
On the videotape, Walter, addressing Peter through the camera, says he sent Peter a letter that contains something of his. Peter asks Walter what letter, but Walter doesn't say anything. Video Walter continues: "I imagine you called me to ask why would you send such a strange letter? And when you tried to call, I didn't answer. So you came to find me at the lab, but I was not to be found." He explains that he was here one moment and then vanished from the face of the earth the next, but he's fine and living many, many years from now.