Simon enters the Situation Room, which I believe means he was chatting with Sophia while walking around the White House. That's a terrible idea. We learn that F16s are twenty minutes away from the silo. Sterling says that the whole Western Seaboard is vulnerable. The stakes have been established.
A guy in a bunker says they're go for launch. Thomas immediately says, "Go." I appreciate that Thomas is trying to get things done. He's not staring into the distance, contemplating the consequences of his actions. The missile's ready? Fire! There's a countdown while people stare at monitors. I understand why Thomas and the people in the bunker are waiting. They know the countdown has begun. The people in the situation room presumably don't know we're ten seconds from launch, so why are they all staring dumbly at their giant screen? Also, when there's no National Emergency Situation going on, do you think they show football games on the twenty screens in there? They could bring in some pizzas and make an impromptu sports bar out of it.
The missile launches in a cloud of fiery smoke. WHOOSH! Sterling asks one of his minions to figure out its trajectory, which is a good idea. Apparently the US is not its target. And the sensors aren't picking up any radiation (I believe this to be nonsense), so it's not even nuclear. We see the missile open up in an orgy of computer animation. It ends up as a communications satellite. And its antennas are oriented ... away from Earth! Sterling: "They're sending a message home." Everyone in the Situation Room has a worried look. The guy from the bunker reports that it's working, and Thomas says, "Send it." Squealy noises fill the Situation Room, so I guess it's jamming communications? Even though we were just told that the antennas weren't even oriented toward Earth? Or maybe it's just emitting a noise so loud that it can be heard through the vacuum of space?
Sean and Leila enter a busted-out records room. Sean and Leila look through half-burnt files, which you'll remember means that they're just throwing papers around without looking at them. At one point, I'm pretty sure Leila picks up the same piece of paper three times in a row. She says she's worried that this is the end of the line and they'll never find Samantha. Sean has a manila folder labeled "Paul Stern," who is Abby's father. There are pictures of him from December 20, 1947. But he looks the same! Leila says that's crazy, because people age. Sean reminds her that Madeline had a theory about aliens who don't age, and Leila says that is also crazy. He wants to think about it, but Leila is getting more and more shrill: I don't wanna think about it! I wanna find my sister!" So now we know that Abby was the daughter of a They. Maybe that's why he was packing!