In the Nash household, a mystical glowing timer hovers above teenage son Eli, decreeing that he will perish the instant he turns sixteen. Consumed by impending doom, the parents dote obsessively on Eli, indulging his every luxury while treating his quiet brother Ash as an invisible domestic servant whose basic emotional needs are perpetually dismissed.
On the night before Eli's milestone celebration, Ash collapses with a life-threatening fever, yet his paranoid parents lock him in a cold basement storage closet to prevent any disruptions to Eli's final hours. As Ash succumbs to untreated infection in the dark, dawn breaks and Eli's countdown timer reaches zero without incident. Unlocking the cellar door, the parents are confronted with Ash's lifeless body, unleashing catastrophic, irreversible horror.
