Ten years ago tests were conducted at a remote cattle ranch in Montana. A small herd was injected with advanced electronic tags; tags that were powered by harvesting energy from any and all nearby sources such as cell phone signals from phones and towers, radio and TV transmissions, electrical power wires, etc. The tags carried with them a capsule containing toxin powerful enough to drop a 1,300 pound animal in a few seconds, then dissipating into an untraceable compound.
Tag Technology, the inventor of the tracking device, had aligned with a government funded group of medical professionals who created the heart attack inducing toxin. Once proven, a program was released to tag every person who entered or exited the California penal system. It soon spread across the nation.
Claire Cory, a Middle East combat veteran and key member of the Tag Technology staff, carries a heavy burden on her shoulders. While in Afghanistan, she ordered the drone attack that accidentally killed her sister. Years later, she’s at the wrong place at the wrong time and is attacked by three gang-bangers. She comes away with physical and mental scars that she believes is her punishment for the death of her sister. Unable to cope, she resigns her job and abandons her fiancé, Kurt Branson.
Her nightmares continue for years until she realizes she needs to return to work to heal. At Tag, she is reunited with Kurt, now a consultant there, and their feelings pick back up immediately. However, she’s reticent initially due to the extreme scars on her chest, thinking Kurt could never love a woman so disfigured.
In an unrelated series of gang war events, one of her assailants is hospitalized. Fearing retribution, he disappears after treatment, but a small necklace falls from his neck on the way out. It’s an odd beaded piece and a doctor who sees it asks that it be analysed. It turns out to be human flesh from 4 different females; Claire being one of them.
Palo Alto Police Detective, Gail Williams, who investigated the original incident with no results, needs to deliver the news; Claire’s severed nipples were found and a BOLO for Lamar Franklin is issued. Claire is again unable to identify photos based on this new lead. What is achieved is a resurgence of bad memories for Claire. She has a difficult time accepting that Kurt can have feelings for her and tries to distance herself by returning the ring he gave her years ago. She wants to be open about her attack but can’t open up. In an emotional evening, she eventually relinquishes and discovers how honest his love for her has remained over the years. He then confesses to having known all along and wanted her to heal at her own pace.
Later, Lamar Franklin is found dead in a car. Claire is brought back to be interrogated by Detective Williams, whose approach is that Claire is now a suspect. Claire gets very emotional, almost out of control, confessing a desire to kill not just Lamar, but all of the perpetrators. In an unusual twist she is able to identify a photo of one of the accomplices; Bobby Jay. Detective Williams hopes she can identify Isaac Hemps too, but to no avail.
That evening at dinner, Claire is torn with guilt over her sister and anger toward Bobby Jay. She confesses to Kurt that she wishes death to her assailants that she wishes she could rid the world of evil. Kurt breaks his code of silence and tell her is consulting job for David is that of an executioner. He receives orders to confirm identities (via the tags) for people in the midst of committing heinous acts and to release the heart attack inducing toxins. She’s initially appalled, but he likens it to her military role with the drones; take an order, kill the bad guys. She warms to the idea and after much convincing, gets Kurt to log into the Tag Technology system and locate the whereabouts of Bobby Jay. She wants to find him and confront him face to face. Kurt tries to convince her it’s a bad idea, refuses to join her. She takes off, eventually spots him, makes her presence obvious, but to him she nobody. Before she can take drastic action, Palo Alto police arrive. She returns home, angered that her “kill” had been stolen when Bobby Jay dropped dead of a heart attack on the street corner. Kurt explains, he didn’t do it…there are many others like him in the same job.
Months later, Claire and Kurt marry, honeymoon in Maui. Kurt gets an order but Claire insists on being the executioner, pressing the terminate button. But the ex-con, who has murdered and is holding hostages doesn’t die. His ‘heart attack’ fails, leading to an unwanted police kill. The toxins are not aging well; it’s a problem.
Kurt and Claire, very much in love, stroll the Hawaiian beach to a bar. As they walk to their seat, a man looks up and recognizes Claire as one of his victims. It’s Isaac Hemps. He’s a born again Christian, vacationing with his wife. He wants to apologize so as they leave the bar they walk by Claire, but she faints at the sight of him. Isaac’s wife, a doctor and a volunteer in criminal rehabilitation, revives her.
Later that night, Claire sleuths her way into the Hemps’ room. Amanda sleeps while Isaac prays. He expected her to come. He asks forgiveness. Claire has no compassion. She induces his heart attack and leaves.
Back home, Claire decides to have reconstruction surgery at Stanford Hospital. She checks in, but her surgeon is called away on an emergency. In recovery, still groggy, her doctor approaches. It’s Amanda Hemps, who explains that the surgery she performed was not the reconstruction Claire expected, but a double mastectomy and hysterectomy and that she had been tagged.