Doug is introduced as an Alaskan oil derrickman who is fired from his job in favor of a Russian crew. He goes to a nearby bar to lament his situation, and ends up assaulted by the very Russians who took his job. To his surprise, Doug finds that he can easily fight back, and dispatches an entire group of them, stunning the other patrons.
Doug fled the bar, but a woman he met there caught up to him and offered to treat his wounds. Afterward, Doug opened up to her about having nightmares of staring at himself in a mirror, and of having foggy memories. She brought out some French wine to ease the conversation, but she sung the French nursery rhyme Frère Jacques while she did, which "awakened" Doug. He stopped responding to the woman, and when he came to, he found himself lying in the middle of the Alaskan tundra with an odd bag by his side.
On his return flight back to the mainland United States, Doug dreamed of being bound underwater and of strangling another similarly bound man. During the dream he sustained an injury to his ankle, and when he awoke, he saw an old scar of that same injury on his ankle. He thenreturned to his home and reunited with his wife Samantha, confiding in her about losing his job. However, he could not shake the memory of a photo he saw when he was activated in Alaska; 37 Sawmill Road, along with the depiction of a woman.
The next day Mike offered to bring Doug in on an illegal pill factory job, which he rejected. Instead he went to "Cloonie's" at the address he found earlier, intending to go day drinking with his wife and to look for the woman in the photo. After coming home he found himself confronted by Lowell, who claimed that Doug "botched his mission in the arctic" by bleeding out a courier and leaving a bag of heroin in the snow.
Lowell insisted that Doug come with him to be "reprogrammed", but Doug refused and so Lowell initiated "clean-up protocol". He attempted to shoot Doug but he managed to disarm Lowell, and the two fought each other until Lowell gained the upper hand. Lowell then prepared to shoot him again but was interrupted by Samantha, who Lowell recognized, but Samantha simply shot him in the head, killing him.
Samantha began to panic, and although Doug tried to assure her that it was self defense that could be reported to the police, Samantha vehemently insisted that they not tell anyone what had happened. Doug relayed that Lowell was after him, and revealed what happened to him in the arctic regarding fighting off the Russians and waking up with blood on his hands in the middle of the arctic tundra after a memory blank. Alarmed, Samantha insisted that they couldn't trust the police and that they had to protect each other. They then agreed to do away with Lowell's body.
Husband and wife drove into the woods to dispose of Lowell's corpse, with Samantha suggesting they remove the "standard ID points"; his hands, feet, and teeth. Although this disturbed Doug, he helped her destroy his body. Samantha quizzed Doug on his encounter with the woman in the arctic, and learned that the woman sung Frère Jacques to him, activating his Cicada protocol.
Doug and Samantha returned home to clean the blood, where Doug found Lowell's suitcase. Inside were files regarding himself, including a blueprint for an infiltration of a pill factory. When Samantha looked through it she found a picture of a woman identical to Doug's own picture, at which point Samantha realized that this woman was Doug's target. She revealed to Doug that she worked in Operation Treadstone and personally trained Doug as a Cicada, an "asset". At Doug's insistence, Samantha explained that an asset was a "low-vis direction action element", sleeper agents designed to go into deep cover and discretely perform missions for the CIA. Angered and in denial over the fact that his entire life was a mere cover story, he left, saying "'us' is a fucking lie Sam".
Samantha later came after Doug and told him that the photo, together with the red circle, is a "post-hypnotic trigger" intended to lock the woman in Doug's mind as his next target. This causes his subconscious to treat the woman like a "problem that has to be solved", which can only be done by completing his mission, a kill mission in this instance. Doug was resistant, but Samantha insisted that with two people having failed to awaken Doug already, the CIA would be sending a team next to capture him. Doug wondered why the CIA wanted her dead, but as Samantha didn't know, the only thing she could tell him was that the voice in his head who he heard singing to him was in fact Samantha herself, singing Frère Jacques to embed it as a hypnotic trigger in Doug's mind.
After driving to the meet up point to join a crew to kill the woman in Doug's photo, Doug asked Samantha how many other assets were out there. Samantha only knew that Doug himself was only the seventeenth, and that she fell in love with him because a part of Doug's old life was still inside him, visible in his eyes. Doug then left Samantha and got in a car with a heist crew.
The crew leader quickly identified their objective to steal the pills from the factory, noting that "Mama Vernon" was inside and probably accompanied by a security detail, and so to be avoided. He insisted that they not get into a shootout and focus on the heist, instructing one of his crew to disable the guards while keeping them alive. However, although the crew didn't trust Doug, he quickly convinced them to change tactics by going in through a ventilator shaft as opposed to fighting their way inside.
On the factory floor Doug noticed Patty Vernon, his target, in an office above the area. To gain access to her through the sea of guards in the way, Doug turned the lights on to reveal his crew and fired off several rounds to engage the crew and the guards in a gunfight. In the pandemonium Doug was able to fight his way up to the rafters where Vernon was, disabling the last of the guards so that the heist crew could secure the take.
With Vernon having fled, Doug continued along the rafters in pursuit of her until Mike shot at him, not realizing who he was. Doug then shot and killed Charlie, a heist crew member, when he arrived to attack Mike. He screamed at Mike to leave and pretend like he didn't see or know Doug at all, so Mike bashfully departed. Meanwhile, Vernon and her retinue of guards had nearly vacated the factory when Doug finally caught up to her, killing her two guards from behind a blinding car light. Doug demanded to know why the CIA wanted her dead, but Vernon claimed they had no knowledge of her and offered to pay Doug to spare her, but instead he just shot her in the head.
Doug returned home conflicted, claiming that when he stopped resisting his training it felt like a whole different person took over and killed without remorse. He feared he had been made into a monster, and although Samantha assured him that he wasn't, he just wanted more answers. He learned from Samantha that she wasn't actually from Boston, that it was in fact his hometown from a life he can no longer remember. He then left to warn Mike about the situation unfolding.
At Mike's trailer, it turns out that Charlie was actually a corrupt policeman, like the heist leader, who Doug ended up killing. When people began moving outside the trailer Doug realized that Mike sold him out in order to avoid going back to prison, which Mike admitted to, so Doug hid behind Mike and allowed him to take the full blast of a flashbang that a SWAT team threw inside.
Doug fought his way out and fled on a dirt bike but was pursued by another policeman, the heist crew leader himself, on another dirt bike. Eventually he managed to crash his bike into Doug's, sending Doug flying into a rough impact that left him knocked out. He then dragged Doug away to rendezvous with Leo Biller, his Treadstone handler who also handled Lowell and Doug.
He complained to Leo when he arrived at having been forced to work with Doug on the heist when Doug not only killed Patty Vernon but got a heist crew member killed. Leo assured him that he'd deal with Doug, but when he turned away Leo shot him in the head, killing him. Doug was unable to stop Leo, who then placed Doug's weapon in the corrupt policeman's dead hand to frame him for Patty Vernon's death.
Leo asked Doug about where Lowell was, having not reported in, and became suspicious of Doug's continued questioning. He suggested speaking with Samantha, at which point Doug attacked and shot Leo before fleeing. However, Leo was wearing a bulletproof vest and was playing possum, so he got up and fled in his car when Doug left, which Doug noticed. He then followed Leo from a distance.
Doug follows Leo to a hotel and uses a makeshift laser recording device to listen in on Leo's hotel room. There Leo reported to Anna Collier about Doug going rogue and another asset being called in to handle Marcus Sachs and his wife. At her continued concerns, Leo revealed that a team would be sent to handle Doug, Samantha, and the police regarding the Patty Vernon situation. Doug also learned that Patty Vernon had $100 million market share in "bootleg opioid pills", which Lang Pharmaceuticals (who Johan Lang would have inherited had he not been killed by Nira Patel) wanted to make into a legal operation.
Doug returned home to report this to Samantha, who he discovered had already redone her identity with a new hair color and a new, untraceable car paid for in cash. She brought out their "go bags", containing passports and other travel items, and fled their house with Doug. On the road he revealed to Samantha that Leo was sending another asset to kill Marcus Sachs, and insisted that they try to save him and his wife. Sachs himself was a mining geologist specializing in rare-earth metals who lived in Arlington, Virginia, so Doug and Samantha went there to help him.
At the house the Sachs family let Doug inside, but an explosion quickly followed, prompting Samantha to run after Doug to help him.
After the explosion Doug quickly roused himself and took command of the situation, stopping Marcus from going to his wife as the asset would be waiting for him to do that. He gave Marcus a gun and told him to stay low while he approached Marcus' wife in a crouch, avoiding a sniper bullet in the process. When he reached Marcus' wife, who was horribly burned from the explosion, he told her to simply be quiet in order to avoid the asset's attention. With everyone inside secured, the asset, Vincent, was forced to come into the house where Doug immediately attacked him.
In the melee Vincent fired off a slew of bullets at random while they grappled until Doug was able to disarm him. Vincent managed to gain the upper hand and send Doug sprawling away, at which point he drew another firearm to kill Doug but was prevented from firing by Samantha's incoming tackle. Vincent shrugged her off and prepared to kill her as well, but she called out his name and evoked memories from before he became a Cicada, stalling him just long enough for Doug to close to grappling range again.
As they fought, Marcus finally made an attempt to flee, shooting wildly toward Vincent but hitting no one. This caught Vincent's attention however and he managed to shoot Marcus in the middle of the fight, badly wounding him. Marcus then crawled over to where Samantha was tending to his wife, and she tried to keep them both alive while Doug continued to fight Vincent. After an intense battle, Doug finally managed to disarm Vincent and put him in a choke hold long enough to allow him to stab Vincent in the neck repeatedly, killing him.
Doug then returned to his wife to find that both of the Sachs' had died from their injuries, Marcus from Vincent's gunshot wound and his wife from Vincent's explosive. Samantha could not save them, and Samantha herself was distraught by their deaths, fearing that she and Doug would end up dead just like them. Samantha claimed that the CIA would inevitably find and kill them, so Doug went over to Vincent with the intention of becoming Vincent's double, being the same height, weight, and of similar complexions.
Using Vincent's corpse to get past facial recognition, Doug accessed and took over Vincent's phone and reported the mission a success. He sent photos of the Sachs' corpses along with a picture of himself seemingly dead, and in response the CIA ordered him to destroy the body. They then destroyed Vincent's body rather than Doug's, and Doug took over Vincent's identity.
Later, Samantha proposed that she would go back to Treadstone to figure out why the operation is active again, as well as to feed information to Doug to keep them both alive. Doug was naturally alarmed, but Samantha assured him that they'd at least hear her out. Doug just wanted for it all to "end", but Samantha insisted that it'd be over when they knew they were safe and back together.
At Vincent's apartment Samantha kept up a running dialogue about Vincent's identity, that he was an art dealer to cover up international flights, that he spoke English, French, Spanish, Portuguese, Russian, Mandarin, and Farsi, that he had an ex wife, that he wrote with his left hand, etc. Doug then shaved himself completely bald to match Vincent's appearance and took more of Samantha's advice to become more like Vincent.
Samantha continued to tutor Doug and even gave him a "pharmacological neuro-receptor antagonist" drug to take. This medicine would supposedly prevent Doug from being forced to comply with his Cicada protocol while under its effects. Samantha also gave him a way to keep in contact, by updating drafts in a dating website. At Doug's questioning, Samantha revealed to him that she gave him a year to develop his new Cicada identity before meeting him and falling in love.
Despite Doug's concern that they would kill Samantha should they discover that "Vincent" is actually Doug, Samantha insisted on going in order to discover what is happening with Treadstone. She worried that with two assets awoken already, the program might be startig up again. Doug also worried about being sent another target and having to kill again, insisting that he was not a killer, and also feared that he'd never see Samantha again. They then kissed, and Samantha left.
Doug then returned to Vincent's home, where he received a mission to kill Padre Vicuna, so he departed for Colombia to carry it out. En route he discovered that Vicuna was opposing the encroachment of a mining company on native lands and was preparing to issue a speech regarding it, leading to him being targeted by Treadstone. Doug reported his travel to Samantha and then arrived in Santa Marta, Colombia, where local Treadstone agents informed him that he had a 24 hour timeline to kill Vicuna.
Doug arrived at a local campsite where he discovered an array of arms and toxins that had been left for him. From the dating website he saw Samantha's message that the Treadstone agents didn't trust her, and came under increased pressure to finish his mission quickly.
When he arrived to meet Vicuna himself however, he couldn't bring himself to kill the man, and so returned to his tent. There he saw a message from Samantha saying he missed his target window, so he once again went back out to hunt down Vicuna.
While Vicuna was praying alone, Doug attempted to sneak up on him only for two mercenaries to arrive and interrupt. They demanded that Vicuna accept the mining company's money and cancel his speech, and Vicuna rejected them, so they attacked him. Doug then fought them off, saving Vicuna, but ended up being stabbed in the process. Vicuna himself tended to Doug's wound, and Doug used a photograph of Vicuna's battered face as "proof" that he killed Vicuna.
After being tended to Doug admitted that he was sent to kill Vicuna, to which Vicuna said that Doug should have simply not interfered with the soldiers killing him. Doug claims that killing Vicuna would keep Samantha safe but make him someone he doesn’t want to be. Vicuna then confirmed that he still intended to give his speech, putting Doug in a predicament.