When you're working undercover the smallest mistake can cost you your life.

When Detective Constable Bailey Morgan's colleague is found dead whilst working deep cover in a women's prison, Bailey steps in to replace her.

Working alone, Bailey embarks on a dangerous journey through the murky underbelly of the prison and soon discovers that Alice's death was part of a spate of brutal murders.

Surrounded by prison officers, criminals and lowlifes, even the slightest mistake could cost Bailey her life as she uncovers a terrifying secret that will truly test her survival instincts.