Joe visits a nursing home seeking a biography subject and is introduced to Carl Iverson, a convicted murderer dying of cancer.

Kathy is arrested for drunk driving and Joe drives two hours to Austin to retrieve his brother Jeremy.

Carl Iverson agrees to give Joe his dying declaration, becoming the subject of Joe's college biography assignment.

Joe pays Kathy's three-thousand-dollar bail at her DUI hearing after she threatens to stay in jail and leave Jeremy unattended.

Joe visits Carl at Hillview, meets war buddy Virgil Gray, and obtains Carl's signature releasing his trial files.

Joe and Lila read the prosecution's opening statement from Carl's trial, which portrays Carl as Crystal's rapist and murderer.

Joe meets Berthel Collins at the public defender's office and learns key case details, including the fingernail found on Carl's porch.

Joe discovers bruises on Jeremy's back and learns that Kathy's boyfriend Larry has been physically abusing him.

Jeremy mentions a typing exercise sentence containing every letter of the alphabet, giving Lila the key to Crystal's coded diary.

Lila and Joe successfully decode Crystal's diary and conclude that the initials DJ refer to Crystal's stepfather Douglas.

Joe and Lila bring the decoded diary evidence to Detective Max Rupert, who reluctantly agrees to reopen the case.

Joe visits Douglas Lockwood at his farmhouse and is attacked with a bottle; Douglas locks Joe in the trunk of his own car.

Joe escapes from the car trunk, flees through frozen wilderness, and hides in a hunter's cabin during a blizzard until found.

Daniel's wife reveals that DJ is a nickname for Daniel, not Douglas, exposing Crystal's stepbrother as her real killer.

Max shoots Daniel dead, Carl's conviction is formally vacated, and Carl dies peacefully in his sleep that night as an innocent man.

Joe visits a nursing home seeking a biography subject and meets Carl Iverson, a convicted murderer dying of cancer who insists he is innocent. Working alongside his neighbor Lila and his autistic brother Jeremy, Joe uncovers evidence suggesting Carl was wrongfully convicted of raping and killing fourteen-year-old Crystal. The investigation leads Joe to decode Crystal's secret diary and bring the findings to Detective Max Rupert and Innocence Project lawyer Boady Sanden. Joe tracks down Douglas Lockwood, Crystal's stepfather, but nearly loses his life when Douglas attacks him and locks him in the trunk of his own car. A shocking revelation exposes Daniel, Crystal's stepbrother, as the real killer, setting up a final deadly confrontation at a remote farmhouse. Carl's conviction is formally vacated before he dies peacefully, bringing justice to both Crystal and the man wrongfully imprisoned for her murder.

The core mystery: from Carl's introduction to Daniel's unmasking.

Joe researches Crystal's murder at the university library and is struck by Carl's expression of confusion in his arrest photograph.

Lila meets Jeremy while helping him fix the television and Joe seizes the chance to invite her to dinner.

While reviewing Carl's criminal file, Joe discovers Carl earned two Purple Hearts and a Silver Star for his Vietnam service.

Joe buys Jeremy a pay-as-you-go phone and tells him to call immediately if anyone tries to hurt him.

Joe confesses to Carl the long-buried story of how he froze and failed to save Grandpa Bill from drowning when Joe was eleven.

Joe and Lila examine fire scene photographs and spot a mysterious face watching from a window of the neighboring house.

Carl reveals that his decision to shield Virgil in Vietnam was not heroism but a disguised suicide attempt rooted in Catholic guilt.

Lila confides that she was drugged and raped at her high school graduation party and shows Joe her self-harm scars.

The morning after Joe stays to comfort Lila, she gives him their first kiss and they prepare breakfast together.

Kathy unexpectedly drops Jeremy off at Joe's apartment and leaves for a casino with Larry for the weekend.

Joe visits Innocence Project lawyer Boady Sanden and presents the decoded diary and other evidence supporting Carl's innocence.

Joe and Lila locate Daniel Lockwood through social media and drive to his home in Mason City, Iowa.

Joe retrieves a garbage bag from outside Daniel's house containing cigarette butts that will yield a usable DNA sample.

Joe permanently removes Jeremy from Kathy's home, breaks Larry's knee on the way out, and walks out on his mother for good.

At Carl's funeral, Virgil gives Joe Carl's war medals; reward money from Daniel's solved murders allows Joe to continue college.

While Joe investigates Carl's case, he uncovers key early evidence including a suspicious arrest photograph and inconsistencies in the trial record that keep his doubts alive. His relationship with neighbor Lila deepens as they work through the evidence together, and she eventually shares a traumatic secret from her past that transforms their connection into something romantic. Joe is repeatedly pulled away from his investigation by his troubled family, particularly Jeremy, who is being physically abused by Kathy's boyfriend Larry in Joe's absence. The couple eventually trace Daniel to Iowa, steal his DNA from his garbage, and Joe makes the permanent decision to remove Jeremy from Kathy's home and cut ties with his mother for good. Reward money from Daniel's connection to other unsolved murders ultimately gives Joe and Jeremy a stable path forward, and Carl is mourned at his funeral as the innocent man he always was.

The relationships, research, and personal struggles behind the investigation.

Lila sees the newspaper article about Crystal's murder and warns Joe that writing Carl's biography will only give a killer notoriety.

Joe meets Virgil separately, hears how Carl saved Virgil's life in Vietnam, and learns Virgil is withholding a second untold story.

Joe views Crystal's gruesome crime scene photographs at Lila's apartment for the first time and is viscerally shaken.

Joe gets a call that Jeremy nearly burned down the apartment while unsupervised; Kathy is missing with Larry.

Berthel reveals Carl refused a plea bargain and demanded a speedy trial, suggesting to Berthel that Carl wanted to go to prison.

Carl tells Joe to look closely at the fire scene photographs and find the difference between images taken before and after firefighters arrived.

Carl agrees to tell Joe the other story from Vietnam, calling it the turning point that changed his entire life.

Joe writes his English assignment describing how Carl refused to rape a Vietnamese girl even as Sergeant Gibbs held a revolver to his head.

After reading Joe's turning point assignment, Lila finally admits Carl is likely innocent and agrees they must focus on other suspects.

Andy Fisher reveals the prosecution completely misread Crystal's diary; her secret distress was about a stolen car hit-and-run, not Carl.

A stranger at the bar publicly humiliates Lila as Nasty Nash with crude gestures; Joe punches the man and the two flee.

Carl confesses to Joe that he murdered Sergeant Gibbs in Vietnam by slitting his throat to stop another rape.

Boady receives early DNA results confirming the DNA beneath Crystal's fingernail does not match Carl's, providing decisive proof of his innocence.

Driving to meet Daniel, Joe secretly dials Max on Jeremy's phone so the detective can overhear Daniel's murder plans in real time.

Daniel's DNA matches Crystal's fingernail and an unsolved Iowa murder, exposing him as a serial killer and validating the entire investigation.

The investigation pivots on a sequence of crucial discoveries that gradually dismantle the accepted truth of Carl's guilt. Virgil's account of Carl's wartime character, Carl's own refusal to rape a Vietnamese girl even at gunpoint, and Andy Fisher's long-suppressed confession that Crystal's diary was completely misread all point unmistakably toward Carl's innocence. Joe's English assignment about Carl's Vietnam turning point finally convinces the skeptical Lila that someone else killed Crystal, redirecting the investigation toward her family. A bar confrontation forces Lila to relive her own assault, drawing her and Joe emotionally closer even as the danger around them escalates. Carl's buried confession about murdering Sergeant Gibbs reveals the guilt that made him welcome imprisonment, while DNA results and a secretly placed phone call to Detective Max Rupert ultimately save both Joe's and Lila's lives in the climax.