Realizing everything he has done causes Dexter to make a drastic decision.
Dexter has to act quickly when Hannah tells him Elway is staking out the airport. He finds a way to get him out of the way but it also leads to the entire airport being closed. With a hurricane bearing down on Miami, few options are open to them. Dexter races to the hospital when he learns that Deb has been shot. She seems to be recovering and he decides to send Hannah and Harrison to Jacksonville where they could catch a flight. A return trip to the hospital leads to Saxon's arrest but also bad news about Deb. Realizing that he has, directly or indirectly, been responsible for the death of everyone he's ever loved, Dexter accepts there is only one option open to him.
Dexter goes to the airport with Harrison to meet Hannah and she tells that Elway is stalking her at the lobby. Dexter uses the airport security system to get rid of Elway but the airport is closed. Matthews calls Dexter and tells that Debra has been shot by Saxon and he heads to the hospital with Harrison; the doctor tells that she is recovering well. The hurricane Laura is coming to Miami and Dexter decides to travel to Jacksonville with Hannah and Harrison using an evacuation bus, but he decides to visit Debra again. Dexter sees Saxon but Angel arrests him but he learns that Debra will stay in coma for the rest of her life. Dexter finds a way to eliminate Saxon in his cell in Miami Metro but feels responsible for the death of everyone he has loved and takes an ultimate decision.
- Dexter and Harrison are at their airport boarding gate, ready to fly to Argentina. Hannah calls from the jet way bathroom. She has spotted Elway and he has positioned himself in such a way that she can't get to their gate without him seeing her. Dexter goes to the store with Harrison and buys some water, pills, and an alarm clock, along with a small bag. He puts the bag by itself and tells an agent he saw Elway leave it intentionally. The woman makes a call and three agents take Elway away for questioning. This allows Hannah the chance to leave the bathroom. Unfortunately Dexter's ploy has forced the airport to ground flights in that terminal.
Debra is placed on a gurney. She is adamant that Angel not call Dexter because she doesn't want him to change his plans. Quinn rides with Debra in the ambulance. She starts talking to him about this perhaps being payback for the bad stuff she's done. Quinn tries to assure her she's better than most people. They get to the hospital and she's prepped for surgery. Debra whispers "I love you Joey" as she is wheeled away. Matthews arrives and Angel tells him about Debra telling them not to call Dexter. Matthews grabs the phone and makes the call.
Dexter gets the call from Matthews as he's walking out of the airport with Hannah and Harrison. He's going to drop her off at the hotel before going to see Debra with Harrison.
With blood pouring from his hand Saxon knocks a man out and steals his truck.
Elway is finally released from airport security and gets on his phone. He finds out that Federal Marshal Clayton has been killed. He thinks Hannah will be finding another way to leave town and makes another call requesting his contacts focus on buses, rental cars, etc.
Dexter is in the room when Debra wakes up from surgery. She seems in good spirits and the doctor says she is optimistic Debra will be fine after some rest. The bullet doesn't seem to have hit anything major. After the doctor leaves Dexter talks to Debra about finding a new way to leave the country. Debra blames herself for Elway sniffing around. Dexter wants to wait until she's better but Debra demands that Hannah leave town ASAP.
Dexter asks Matthews to put extra security on Debra's room.
As Dexter and Harrison leave the hospital they run into Elway. He makes a crack about Hannah and tells him not to go down with her. Elway then suggests Dexter is partially responsible for Clayton's death.
A bloodied Saxon walks into a vet hospital and pulls a gun on a vet. He demands the man stitch him up.
Dexter is still worried about Debra. Hannah suggests she and Harrison take a bus and go ahead, leaving from a different city.
The vet finishes up Saxon's arm. They both see a TV report about Debra's shooting. Saxon tells the vet to grab his keys.
Dexter puts Hannah and Harrison on a bus. Dexter says he can't get on with Saxon still loose, and says his good-byes.
Saxon and the vet pull up to the hospital. He asks Saxon to be let go, saying he promises not to talk.
Cut to the vet staggering into the hospital with blood pouring out of his mouth. Saxon has cut out his tongue and used the distraction to sneak by the front entrance. Dexter follows just behind him and realizes instantly what is happening. Dexter runs into Saxon just outside Debra's door but before he can do anything Angel puts a gun to Saxon's head and he's placed under arrest.
Dexter walks into Debra's room and finds it empty. He finds a visibly shaken Quinn who tells him Debra took a turn for the worst. The doctor tells them that a clot caused Debra to have a stroke. Based on brain activity tests she will never be herself again.
Dexter again flashes to seeing Harrison for the first time with Debra. She tells him she's confident he'll be a great father because he was such a good big brother to her.
Sitting on the bus Hannah and Harrison talk about Argentina. A hand grabs Hannah and she looks over to see Elway. One of his contacts tipped him off that she was there. He'll ride with them to the next stop, where they will get off and he'll turn her in.
Dexter watches Angel and Quinn interrogate Saxon, who quickly lawyers up. Dexter thinks that he can easily leave Saxon to the legal system, which will no doubt execute him.
On the bus Hannah offers Elway a cup of tea. He turns her down, but the moment provides enough distraction for her to jab him in the knee with a horse tranquilizer. She and Harrison will be getting off, while Elway will sleep in his seat for several hours.
Dexter arrives at the jail and tells the desk he's there to conduct a gunshot residue test on Saxon. The person says if he needs help to hit the red buzzer. Dexter sits across from Saxon and says he'd like to be able to blame him for what happened to Debra. But Dexter thinks it's "all my fault." Saxon has forced Dexter to evaluate his life and decide there is no way he can live a happy life. Dexter says he's there to kill Saxon with the pen he's just placed on the table. Saxon grabs it and jams it into Dexter's shoulder. Dexter pulls it out and sticks it into Saxon's neck. Dexter stares blankly at his body for a second before hitting the security button and falling backwards into the wall. He assumes a fearful voice and tells guards "he tried to kill me."
Angel and Quinn watch the security footage of Dexter killing Saxon. Angel has several legitimate questions about why Dexter would be there since he no longer works for Miami Metro and this person has shot his sister. Dexter says he's still technically on the department's payroll for the rest of that week and Saxon shooting Debra was precisely the reason he was there, since he wanted to ensure the case was processed perfectly. Though both know that Dexter deliberately killed Saxon, Angel and Quinn are fine with that and let him free.
With the storm about to touch land, Dexter takes his boat to the hospital, which is in the middle of moving patients to safer areas because of the hurricane warning. He is able to walk into Debra's room unnoticed. He grabs her arm and apologizes. Dexter thinks that as a good big brother he can't let her live like this and disconnects the machines. Just before Debra dies Dexter whispers "I love you" into her ear. He wraps Debra in a sheet and puts her onto a gurney. Due to the chaos outside, he is able to take her onto his boat. Dexter calls Hannah, catching her and Harrison as they are boarding their flight. She seems happy about their future. She gives Harrison the phone and Dexter tells his son that he loves him. Dexter then tosses his phone overboard and drops Debra's body into the water. We hear through his voiceover that Dexter believes he destroys everybody he loves and must protect Hannah and Harrison "from me." He turns the boat and drives directly into the storm.
After the storm has passed, a coast guard boat finds a piece of Dexter's "Slice of Life" boat floating in the water. Angel gets a call that Dexter is believed to have been killed in the hurricane.
Sitting at a café in Argentina, Hannah reads a news article reporting Dexter's death. She sheds a tear and then leaves the café with Harrison to get some ice cream.
In the final scene, we see a bearded Dexter working as a trucker in logging country. He leaves his haul and walks into a rental home. He sits at a table and the series ends with him staring into the camera.