Windmark's back in 2036, it seems, and his assistant is reporting that after the invasion, September was detained at a mine in Pennsylvania, extracting rocks, but the purpose of the rocks was not determined. "He was questioned and released. He was labeled a known offender," says the Observer, which means, points out Windmark, that he's been tagged. He tells the assistant to initiate "location protocol" to find his address, and the assistant comes up with chip number 784651.
And Windmark pops right into September's apartment, with a couple of backup Observers. He orders them to search the apartment, and his two flunkies spread out, finding blood and tweezers in the kitchen sink. They report back to Windmark that September has most likely removed his chip and destroyed it, which is likely why they couldn't track it. Windmark picks up a cup of tea from the table and notes it's still warm, meaning September was just here. He orders his men to have the Loyalists review footage from surveillance cameras in the area. He passes through a doorway, not noticing the little device with flashing red and green lights on the wall above the threshold. He inspects a bible and a New York City snow globe, with the Statue of Liberty ludicrously out of scale in the skyline. More quality control at the snow globe factory, please! Then he powers on the stereo, which starts playing some jazz that my Shazam app will only identify as belonging to Fringe.
Meanwhile, in an ancient minivan -- I suppose this season's storyline has eliminated the possibility of lucrative sponsorship deals from fancy electric vehicles -- the group pulls up at a storage facility. Walter tells Peter and Olivia to stay in the van while he and Donald go to get the tech, and then September's comm starts beeping. He pulls it out and then shows the rest of the group video of Observers in his apartment. "You can't go back there," says Walter. "There is no 'back there,'" says September, and he pushes a couple of buttons on his phone.
Back at the apartment, Windmark the hepcat is still listening to the jazz, when one of this men comes back in, and Windmark appears slightly surprised to realize his underling is tapping his foot along to the beat. The underling is as surprised as Windmark, but before they have time to contemplate the implications, they notice the flashing device above the doorway, which goes from flashing green to solid red. And as the apartment fills with light, noise and heat, Windmark and his underling flash down to the street below -- no sign of the second underling -- and gaze back up at the apartment, now a smoldering crater.