When ten prisoners are mysteriously found dead in their beds across eight different wards—with no signs of struggle or cause of death—the prison turns into a crime scene cloaked in silence and fear.

The surviving inmates claim ignorance, the guards are baffled, and time is running out.

Intelligence officer Selin Korkmaz and homicide captain Erol Haktan are called in to investigate.

Quarantining the prison, they begin a meticulous and harrowing inquiry, unlocking hidden layers of conspiracy and psychological torment.

As they peel back each “lock” in search of the truth, they uncover a darkness far greater than they imagined—one that may not be contained within the prison walls.