Although we're on the edge of our seats after the previous episode's reveal that Peter has a new partner as sanctioned by President Hagan, The Night Agent season 3 episode 4 opens with a flashback to 15 months ago. Theo strikes out with giving Jenny a decent speech for an event, but Chelsea steps in to give her tips that make her look like a relatable mother in a room full of women. It works, endearing Chelsea to Jenny, and furthering Theo's interest in Chelsea, too.
Back in Peter's apartment, he sits at his table with Adam. He still doesn't trust him and calls Night Action to prove that he's legit. Peter finally speaks directly to Mosley, who knows of Adam's existence but doesn't know why he was assigned to Peter. Realizing Hagan has ignored protocol, Peter supposes Adam's either a spy or babysitter. But he has to trust him with details of the investigation — to a certain point. He will look into Walcott Capital while Peter works another angle.
In the White House, Chelsea spots Jenny picking up the attacker's phone from her couch and hiding it in her desk drawer. Chelsea's debriefed on the intruder, Brian Mott, a former White House butler, but there are further details that need to be ironed out. She's sent home, requiring a psych evaluation before officially returning to work. Back at home, Chelsea expresses her doubts to Theo about the First Lady not pressing the panic button. He insists she shouldn't read into it.
Chelsea questions the First Lady's intentions
Meanwhile, Peter and Isabel come up with a new plan to speak with Senator Lansing by using Mike's suspicious death as a bargaining chip. Isabel's immediately patched through to Lansing, who invites her to his retreat upstate. He's sending a helicopter to pick her up at noon. Peter drops her off at the heliport and promises that he will meet her there as soon as possible.
When Jenny thanks Chelsea, she tries to get more information out of the First Lady, but she's not forthcoming with rehashing the events of the altercation. Isabel arrives at Barrow Lodge and gets the tour before being show to her room. She's set to meet with Senator Lansing for dinner later that evening, and as promised, Peter arrives shortly after under the guise of a job interview. Isabel buys him new clothes from the lodge's boutique to help him blend in.
Chelsea watches Theo give a press briefing about the First Lady's attack, which ends with Chelsea being thanked by name. She's furious that her name is linked to a false story about the intruder being armed, but Theo was under orders by POTUS and FLOTUS. The story was fabricated ("spun") to help contain in it as far as the public is concerned. Isabel pushes Lansing to comment for the story, but he refuses when he fails to get her to drop it. Also, surprise, the assassin is at the lodge.
The assassin takes out Lansing and closes in on Peter
Peter follows Lansing to a private house called Anchor Point after his dinner with Isabel where he speaks heatedly without mysterious figures. Back in Isabel's room, Peter hesitates on sharing his theory about the donor when Isabel receives another invite from Lansing for the next morning. In the meantime, Peter and Isabel play pool and get to know each other better. She reveals that her father has money and isn't sure how she feels about him. He abandoned her but paid for her college.
The next morning, Isabel meets with Lansing. They go for a walk outside, and she's concerned when he brings a rifle. Peter learns that someone named David Hutson owns Anchor Point then rushes to catch up with Lansing and Isabel. Now deeper in the woods, Lansing admits to working with a donor but doesn't know much more about the funding of the attack. Isabel insists on printing the truth, and he points his rifle at her. Peter arrives in time to stop him from shooting her.
However, as Lansing apologizes to Isabel with Peter's pointed at him from behind, Lansing gets shot in the head from a completely different direction. In the woods, the assassin's son sees him running with a gun. Peter and Isabel get back in his car but quickly realize the breaks have been cut. They crash into a boulder and are forced back on foot when gunshots from the assassin fire in their direction. Peter throws Isabel's phone into the distance, calls it, and they run away.
In spite of his head wound, Peter leaves a trail of blood in one direction and sends Isabel away to safety. Peter ends his trail, lying on a rock and pretending (hopefully) to be dead. Just as the assassin approaches him, Peter opens his eyes bracing for the gunshot. The assassin gets shot in the arm and dashes away before he can get caught by whoever shot him. On the brink of passing out, Peter lies on the rock and looks at the sky. Adam enters his vision, clearly the person who saved him.