Truth or Dare

At an end-of-term Halloween house party, Felix arrives alone while a group of friends gathers. He watches Gemma from a distance, catching Luke's eye and setting a troubled tone for the night. Luke provides Felix with cocaine and pushes him to talk to Gemma, aware that it will have consequences.

Felix asks Gemma out, but she declines politely. Chris taunts Felix and punches him, escalating the tension among the group. Gemma dumps Chris and goes to comfort Felix, deepening the connection between the two.

Months after Christmas, the five friends receive an invitation to Felix's surprise birthday party. They drive to Felix's mansion and eventually make their way to a secluded forest shack behind the estate. There, they meet Justin, Felix's elder brother and a hardened veteran who immediately makes his presence felt.

Justin reveals that Felix hanged himself the night after the Halloween party, and that a postcard reading 'Truth or Dare, bitch!' fueled his despair. He asserts that no one can leave until they uncover who wrote the postcard, arguing that uncovering the truth will redeem the family’s honor. The revelation sets a vengeful tone for a deadly game.

The Acid Test begins as Justin forces the group to participate in a gruesome version of truth or dare. Gemma is fed through a tube connected to two jars—one containing water and one acid—and Chris is ordered to choose first, picking the water jar. Justin then swaps the jars and makes Paul choose; Paul drinks the acid and Chris chokes to death on his own blood.

Gemma takes advantage of a distraction and loosens her binds, escaping through the back window into the woods. She runs toward help as the night tightens around the shack.

Jonesy, Luke's drug-dealer friend, appears at the shack door and refuses to leave. Justin breaks Jonesy's arm and pressures Luke to shoot him; Luke fires, killing Jonesy, while Gemma's escape continues in the background.

Gemma reaches Felix's mansion seeking help and discovers him alive but bed-ridden. Woodbridge the groundsman confronts her, revealing that he found Felix hanged and has been caring for him since his deathly collapse. A tense confrontation leaves Woodbridge fatally wounded.

Justin arrives at the mansion and murders Gemma, breaking her neck in front of Felix and taunting his brother with the grisly scene. The brutal act underscores the ruthlessness fueling his mission for 'justice'.

Back at the shack, Luke insists on staying loyal and reveals he sent the incriminating postcard. Eleanor bites off Luke's finger, sending him reeling, and he fatally impales himself on a nearby tool.

Paul and Eleanor free themselves and attempt to escape. Justin returns with Felix in a wheelchair, and a brutal fight erupts: Eleanor shoots Justin and smashes a jar of battery acid over his head.

Eleanor reveals the true motive behind Felix's suicide was blackmail over a sexual incident involving Felix and Paul; she gives Felix a grenade and escapes with Paul. The house then explodes, killing both Felix and Justin.