Duncan Moore is in the house. Actually, he's in the precinct. The guy's officially back on duty. He asks to ride with Andy, but Nick volunteers to babysit the inept rookie instead. In other news, Holly has a problem with a case, or so she says. It's really just a ploy to get Gail alone in an interrogation room so they can make out. Holly wants to talk with her about their relationship. Gail can't do it right away. She has a thing.
The Commissioner's Gala is on the horizon. Andy bought a new dress for it. She'll be wearing something special under it for Sam, who has something special for her, too. It's a key to his apartment. Andy politely declines the offer. She doesn't want to mess up how good things are at the moment. Out on the streets, an explosion rocks a city. It comes from inside a parking garage. Andy and Chloe find the source of the blast. Andy finds an unconscious woman near a car that was wired for bombing.
A car jumped the garage toll just before the explosion. Dov notices Chloe and Wes getting chummy during the investigation. The bombing victim, a student named Brianna Kelly, doesn't own the car that blew. She's the daughter of Aiden Kelly, the head of the Irish mob. Another bomb goes off at an intersection downtown. There are many more casualties including Aiden Kelly's second in command. Sergei Melakov and his crime family are the prime suspects in the bombing.
Andy remembers seeing the car that jumped the toll at the apartment tenement they cleared out in "Moving Day." She gets the plate number off the body cam footage she shot. Duncan watches her work after his offer to help is dismissed with extreme prejudice. Dov is able to pull up the driver's face in what's left of Chloe's footage, as some of it has been deleted. The guy in the video is the same man who got in Andy's face about his bike being stolen.
Duncan gets a phone tip on the case. He takes off without telling anyone where he's going. Duncan finds the suspect's car in a driveway. He's then knocked unconscious with a heavy wrench. Back at the station, the suspect is identified as Theodore McDonald. The car he was driving is registered to his 75-year-old mother. Andy and Nick are off to investigate. They have no idea that McDonald is holding Duncan prisoner.Four years ago, Theodore McDonald was a victim in a bombing at a diner. His son, 12-year-old Brendan McDonald, didn't survive the attack. Andy and Nick see Duncan's car outside the suspect's house. They search the garage to find a Duncan cuffed inside a truck that's wired to explode if he opens the door. There's less than 10 minutes before it blows. That's not enough time for the bomb squad to hit the scene. Nick has some experience in this area. He orders Andy out of the garage while he tries to disarm the bomb.The bomb squad talks Nick through the procedure. Duncan talks to Andy over the radio. He apologizes for all his screw-ups. He admits that he froze when he was supposed to be backing her up. He admits he's not a real cop. Duncan's radio goes dead and Nick continues to work on the bomb. It's not looking good. There's only a minute left. Nick uses bike tire rubber to insulate the detonator. Time's up. The bomb doesn't blow. Nick did it! Everyone is safe.
Dov confronts Chloe about the deleted body cam footage. She comes clean about her kiss with Wes. Dov no longer believes he can trust her. Oh, and that thing Gail had, it was about trying to adopt Sophie, the little girl who was orphaned when her mom was killed in "Wanting."
Nick lets Andy know that there are no unresolved feelings between them. Duncan had said something earlier that suggested otherwise. Andy admits that she's happy with her current love. Speaking of Sam, his ex, Marlo Cruz, arrives on the scene to help with the case. She part of the Intelligence department. They need to work together to hunt down McDonald, who is still out there with explosives and a vendetta.