Peter Houghton opens fire on students and staff at Sterling High School, killing ten people in nineteen minutes.

Patrick Ducharme rushes into Sterling High against protocol, follows the gunshots, and subdues Peter Houghton in the school locker room.

Patrick carries a traumatized Josie Cormier out of the locker room, initially believing her to be dead.

Alex Cormier adjourns her court when told of the shooting and races to Sterling High to find Josie.

Lacy Houghton arrives at the crime scene and learns from a student that her son Peter was the shooter.

Patrick questions Peter in a holding room and gets only one response from the silent teenager: 'they started it.'

Lewis Houghton calls Jordan McAfee, who agrees to represent Peter despite initial reluctance, believing Peter deserves a fair trial.

Peter is arraigned on ten counts of first-degree murder and nineteen counts of attempted first-degree murder.

The community holds funerals for the ten victims; Josie walks to the podium at Matt Royston's funeral and breaks down crying.

Patrick watches surveillance footage of Peter calmly eating cereal and wearing a dead student's headphones during the rampage.

Jordan and Selena develop a defense theory that Peter's shooting was a symptom of battered-woman syndrome caused by years of bullying.

Diana Leven opens the trial recounting Peter's rampage; Jordan argues Peter acted in dissociative self-defense as a chronically bullied child.

Josie takes the witness stand and confesses that she was the one who first shot Matt Royston during the attack.

Peter is convicted of eight counts of first-degree murder and two counts of manslaughter for the deaths of Courtney and Matt.

Alex resigns from the bench and returns to defense work; Josie is sentenced to five years in prison for her role in Matt's death.

Peter Houghton opens fire at Sterling High and is stopped by detective Patrick Ducharme, who disarms him in the school locker room and carries a traumatized Josie Cormier to safety. The town of Sterling reels as families bury ten victims and investigators piece together how a quiet teenager became a mass shooter. Peter is arraigned and publicly demonized while his lawyer Jordan McAfee mounts an unlikely defense, arguing that years of relentless bullying drove Peter to a breaking point. The trial arrives five months later, with prosecutor Diana Leven painting Peter as a calculated killer and Jordan countering that Peter acted in dissociated self-defense. A shocking last-minute confession from Josie Cormier upends the trial and forces the court to reckon with a far more complicated truth. The verdicts that follow carry consequences for nearly every person touched by the nineteen-minute rampage.

The headline events of the Sterling High shooting and its legal aftermath.

Lacy delivers a baby while musing about where childhood innocence goes, unaware her own son is preparing to commit violence.

Alex rushes to the hockey rink and scans a posted list, finding Josie's name among the wounded.

Peter and Josie share their first day of kindergarten; an older student throws Peter's lunchbox out the bus window and Josie offers to share her lunch.

Lewis and Lacy wait outside their home during a police search and discover that several of Lewis's guns are missing from the locked cabinet.

Patrick and ballistics technician Selma determine that Matt Royston was the only victim shot twice, once in the stomach and once in the head.

Josie flushes the Ambien pills she had stolen from her mother down the toilet, realizing that death is not an answer.

Lacy visits Peter in jail and discovers that the sullen, rude young man before her is not the son she thought she raised.

A forensic tech reveals that Peter hacked the school's network to display 'Ready or not...here I come' on every computer screen at once.

Yvette Harvey, mother of shooting victim Kaitlyn, shoots herself dead inside a gun store while the town is still reeling from the attack.

Alex takes Josie to a diner to bond, but a car backfiring outside triggers Josie's trauma and forces them to leave immediately.

Jordan places Josie on the defense witness list, forcing Alex to acknowledge she cannot remain impartial and to recuse herself from the case.

Drew arrives to testify, denies ever bullying Peter, and Patrick grabs him by the throat and threatens arrest until he admits the truth.

Lacy breaks courtroom protocol to walk over and caress Peter while testifying, then a victim's father shouts expletives at her from the gallery.

Patrick traces the trajectory of a second bullet during the trial and finds it lodged in a maple tree outside the gym window.

Lewis returns to university teaching and switches his academic research from the economics of happiness to the impact of school shootings on communities.

On the morning of the shooting, ordinary life in Sterling continues as Lacy Houghton delivers a baby and Josie heads to school, until everything shatters in nineteen minutes. In the aftermath, investigators uncover troubling details: Matt Royston was uniquely shot twice, Peter hacked the school's computers to display a chilling message, and Lewis's guns were missing from the cabinet before the attack. The community strains under grief, with a victim's mother taking her own life and Josie secretly disposing of pills she had hoarded for suicide, while Alex's attempts to reconnect with Josie repeatedly fall short. As the trial approaches, relationships fracture under pressure—Lewis becomes estranged from Peter, Lacy faces public blame, and a key witness is caught lying about bullying until Patrick forces him to tell the truth. A bullet Patrick traces to a maple tree outside the gym window proves decisive in sorting out what actually happened in the locker room. By the end, the full cost of nineteen minutes becomes clear as careers are remade, a family buries two sons, and Lewis quietly redirects his life's work from studying happiness to studying harm.

The community's unraveling and the hidden details surrounding the shooting.

Alex, pregnant and without a partner, decides to keep her baby after Lacy shows her an ultrasound and she breaks down crying.

Alex and Lacy discover Josie holding a rifle from Lewis's unlocked gun cabinet and Alex ends the children's friendship immediately.

Lewis teaches Peter how to handle and clean guns, telling him a gun's power comes entirely from the person who wields it.

Josie visits Courtney Ignatio's house for a school project, tries on Courtney's makeup, and hears for the first time that she looks good.

Peter goes hunting with Lewis and deliberately misses a deer because he cannot bring himself to kill anything, while Lewis quietly covers for him.

Peter presents a class chart ranking social groups and labels Josie a 'bridge,' humiliating her publicly in front of Matt and the whole class.

Matt physically grabs Josie at a party and leaves bruises on her arm, then tells her he loves her and she forgives him.

Peter visits a gay bar to test his sexuality and is nearly taken advantage of before Mr. McCabe intervenes and drives him safely home.

Trapped in a stuck elevator, Josie kisses Peter on a dare and confesses that Matt has been hurting her, swearing Peter to secrecy.

Courtney reads Peter's heartfelt email to Josie and has Drew forward it to the entire school without Josie's knowledge.

Matt publicly pulls down Peter's pants in the school cafeteria, exposing him in front of the entire student body.

Josie discovers she is pregnant after Matt has unprotected sex with her without consent while drunk, and later miscarries.

Peter sees the forwarded email reappear in his recycle bin on the morning of the shooting, snaps, and packs pistols into his backpack.

Josie recovers her full memory in Jordan's office and reveals that Matt fired at Peter first before she shot Matt in the stomach.

Peter tells Jordan he kept Josie's role in the shooting secret because friends do not tell on each other.

Long before the shooting, the seeds of tragedy were planted in Peter Houghton's childhood—from a friendship with Josie Cormier that slowly unraveled under social pressure to a troubled relationship with guns introduced by his own father. As Peter and Josie entered adolescence, their worlds diverged completely: Josie drifted toward popularity through Courtney Ignatio, while Peter was systematically excluded, humiliated, and abused by the very group she joined. Matt Royston's public cruelties toward Peter intensified over the years, while his private abuse of Josie went unseen by everyone around them. Peter finally reached out to Josie in a heartfelt email that Courtney intercepted and spread to the entire school, leaving Peter utterly alone and exposed on the day of the shooting. When Josie recovers her full memory during the trial, it becomes clear that the story of what happened in the locker room was never Peter's alone. The truth about who really fired first forces the courtroom—and the reader—to confront how far the damage of one school's culture of cruelty had quietly spread.