After a woman named Betty Wright has a single-car accident, a man rushes her to the hospital, sits her down at a tree just outside of the hospital and then shoots her, leaving her brain-dead.
Earlier that day, a man named Cliff Daniels was bludgeoned and shot to death on the steps of a church. The same gun was used in both shootings.
Rossi receives a call from New Directions for Veterans, only to learn that his wartime Sergeant and friend Harrison Scott has died of cancer.
The unsub calls 911 to report a shooting, drops his cellphone into a garbage can, and then shoots a man named Victor Hall. Hall had just been to see a psychiatrist named Peter Goodwin, who witnesses the shooting.
Goodwin provides a description of the unsub to Hotch. He also tells him that there were police sirens sounding before the shooting took place.
Rossi phones his daughter Joy to tell her that he's going to be late in getting to her place for a visit.
Reid and Kate go to the medical examiner who tells them that the gunshot didn't kill Hall - the bullet just grazed his skull. He was killed by the blow to his head before the gunshot.
Rossi has a flashback to his time in the war with Harrison Scott, in which Scott brings Rossi a Purple Heart medal as he lay wounded in the medical unit.
Scott's son Thomas tells Rossi his father had been sick for a year - and had warned him not to tell anyone, especially Rossi. Rossi offers to take care of the funeral.
The unsub's daughter finds him yelling at the TV set as they display the body of his latest victim being covered up. She talks with him, apologizing for putting him and her mother through so much when she was on drugs.
The unsub later breaks into someone's home, and calls 911 to report a burglary and assault. He sees lots of prescription bottles and empty bottles of booze. The homeowner confronts the unsub who shoots him while saying "you should have stayed asleep".
The team determines that the unsub is warning emergency services prior to hurting people.
The unsub's daughter brings a man named Keith Doheny home - man she met at her group. Doheny is sick and in need of a liver transplant.
The team realizes that all of the victims were organ donors. He killed them in such a way as to make sure they could be found early enough for their organs to be harvested.
The unsub's daughter is in need of a liver transplant.
The unsub realizes that Keith is about to be set up for a liver transplant - a transplant he believes should go to his daughter. He kills him. Afterward, he arrives home to find his daughter Estelle passed out on the floor.
A doctor at the hospital warns the unsub his daughter doesn't have much time left.
Joy meets Rossi at New Directions for Veterans, surprising him. He tells her some stories about his times with Harrison Scott.
Hotch realizes that the common thread tying all the victims together is the DMV - where the unsub works.
Garcia identifies the unsub as Frank Cosgrove and gives his work address to Hotch and Morgan.
Cosgrove takes a picture of a new driver named Carol Murray and realizes she's an organ donor.
As they rush to the DMV, JJ calls ahead and finds out that Cosgrove has left for the day, right after Carol Murray has left the DMV.
JJ calls Carol, just as Cosgrove grabs her and holds a gun to her head.
Right then they arrive at the DMV. JJ and Morgan try to talk him down and warn him to drop his weapon. Instead, he pushes her away and shoots himself.
Estelle wakes up to find she's being taken to surgery to receive a liver transplant. The donor was her father.
The episode ends with a full-honor Marine funeral for Harrison Scott.