Sophia discovers that Martinez is about to start killing everyone in the cathedral, so she has her remote portal operator blow up the Washington Monument. This provides enough leverage for Martinez to cancel the killing plan and provide three buses. But Sophia explains to Simon (who it turns out has been at the White House this whole time, but he wasn't paying attention during last week's episode) that it was all a bluff, because they're out of portal juice. Unfortunately for her, this is the exact conversation that gets decrypted once Sterling tells Martinez that Simon is definitely one of Them, because he just realized he recognized Thomas from that elevator ride earlier in the season. As you can tell, plot twists are coming at us fast and furious at this point, but the result is that two of the buses get blown up, killing Isabel and Thomas, who has decided to sacrifice himself for Sophia. Sophia's bus goes through a portal (this was later, so they had more juice) and vanishes. Martinez seems mad, but at least he got to kill over a hundred aliens. You usually get an extra life for that kind of performance
Sean and Leila take a private jet to France, where they meet up with the friendliest, Frenchest, drunkest contact you've ever seen. His name is Henri. They don't do much except drink. Meanwhile, Dempsey kills an archaeologist and seems very interested in old jugs and cave paintings.