Brother

USMC officer Sam Cahill is preparing to leave for Afghanistan in 2007. He is married to Grace and has two young daughters. A tense family dinner introduces tensions with Sam's brother Tommy, who has just been released from prison, and with Hank, their father-in-law who belittles Tommy's past and loyalty to Sam.

During Sam's tour, his helicopter is shot down and he and Private Joe Willis are the sole survivors. They are taken prisoner by the Taliban and later declared killed in action by the U.S. government. The news devastates their families and sets the stage for a brutal captivity.

Back home, Grace receives the news and Tommy confronts her about letting Sam go. At Sam's memorial service, Hank's drunken misbehavior surfaces, and Tommy challenges him about the past and his influence on Sam. The family fractures under the weight of loss and resentment.

While Sam is missing, Tommy helps Grace with a kitchen remodel and begins to mend relations with Hank. He bonds with Grace and Isabelle, and his growing paternal connection with Sam's daughters softens the family dynamic. He also makes amends with a bank teller from his past mistake.

Grace and Tommy grow closer during the time Sam is away and share a kiss. They do not pursue the relationship further, but the moment deepens the emotional tension between the two families. The kiss hints at temptations that threaten Sam's trust upon his return.

In captivity, Sam and Joe are subjected to harsh torture. To survive, Sam is forced to brutalize Joe, ultimately killing him with a metal pipe. The act binds Sam's fate to his actions in the camp and weighs on him after he returns home.

Sam is rescued after months of captivity and returns to his wife and children. He struggles to readjust, showing signs of severe post-traumatic stress disorder and increasing distance from his family. He also lies to Joe's widow about his death, compounding the family's pain.

Sam's paranoia grows as he questions what happened while he was away. Grace tells him she and Tommy shared only one kiss, but Sam has trouble accepting that explanation. The tension erodes trust and fuels his fear of losing Grace and his family.

During Maggie's birthday party, Tommy arrives with a woman named Tina, while Isabelle vents about feeling neglected by Sam. She pops a balloon in rage and later falsely claims that Tommy and Grace are having an affair, saying she wishes Sam had died. The event heightens the house's emotional volatility.

After the party, Sam becomes enraged and wrecks the kitchen with a crowbar in front of the family. Tommy arrives to help calm him, and Sam briefly embraces him before turning defensive and pointing a gun at him. Police arrive, leading to a tense standoff and Sam's surrender.

Sam is arrested and admitted to a Veterans' Affairs hospital. Grace reads the letter he wrote for her and confronts him with an ultimatum to tell the truth. He finally confesses that he killed Joe, and they share a hopeful moment amidst the trauma, wondering if they can ever return to normal life.

With the confession and the ordeal behind them, Sam and Grace face an uncertain future. He remains devastated and traumatized by his war experiences, unsure whether he can ever live a normal life again. The film closes on a note of fragile hope and ongoing healing.