After the commercial break, Peter is still telling Lisa she doesn't have to do this. Well, I shouldn't say "still." 24 has ruined me for other shows; I assume the clock is running during commercials. "I already told you to leave once. I am not gonna tell you again," says Lisa/Rusk. Tsk. You've already lost that battle, Rusk. You have to be willing to back up your threats, or Peter will walk all over you!
And Peter starts in with the sob story about how he knows what it feels like to be different. "I was always sick. I didn't have any real friends. I lost my virginity to my English teacher, Ms. Jacobs, and everyone found out, and she had to leave town..." Rusk is annoyed and confused and I think even Teresa on the ground is all "shoot me now!" but Peter's talking to Lisa: "You've been given a second chance here, but you have to fight for it."
Rusk is understandably about to blow Peter's head off, which is when Charlie, from behind, shoots Lisa with a syringe, which fortunately for Peter contains what appears to be some sort of instantaneous paralysis-inducing sedative, as Lisa collapses immediately.
Outside, a groggy Lisa is being wheeled into an ambulance and she asks Peter what happened. He says he'll tell her later, and Olivia tells her that the ambulance guys are going to take her to the hospital and check her out and make sure everything's OK, like she's SEVENTEEN, Olivia, she knows what the deal is with the ambulances. She tells Lisa that after that the ambulance guys will bring her back to the lab INSTEAD OF HOME, I GUESS.
After Lisa is loaded up, Olivia asks Peter how he knew he'd be able to reach her, and he quotes from the Tibetan Book of the Dead: "Innermost subtle consciousness is ever present. It never leaves the body even in death." And Olivia needles him over getting a lot of "mileage" out of a "coaster" and then Peter says he threw up a Hail Mary.
Back at the lab, Walter has finished checking out Lisa's brainwaves, which look perfectly normal to him, which means Rusk's gone. Walter figures Rusk just stuck around "to deal with unfinished business" and once he did, Lisa was able to purge him. Which is a great theory except it should be pointed out to Walter that Rusk never did kill Teresa, so his business, as it were, is still unfinished. And then Walter quotes, in Latin, from the Bible, and Ms. Donovan doesn't speak Latin but when Walter says it's Isaiah 7:9, she nails it: "Unless you believe, you will not understand." And she practically tears up and Walter talks about sometimes needing to rely on faith even as a scientist, and Ms. Donovan is all, "God keep you and yours safe, Mr. Bishop," and I could be crazy but I think Ms. Donovan is digging Walter's action.