

Sister betrayed, suspect seduced, city terrified — and she's holding all three secrets.
Season 1 • Episode 2
LatestJay follows up on the theory that a suspect could be the man they are looking for, and when bank statements confirm that the payslip found at the scene of one of the assaults belongs to him, Wilson organizes an arrest.
Ali Pearson is an English law officer simultaneously involved in a heated and clandestine relationship with her sister's beau and a city-wide police hunt for a serial rapist. When the squads close in on the boyfriend as their prime suspect, it foretells Ali's need to 'lay down her cards' by confessing her relationship to the man in question. But this may mean permanently losing all ties with her sister. Ali suddenly finds herself torn violently in two directions - but she's quickly running out of time, as new details come to light regarding the suspect's background and motivations.
Acting
Sarah Parish's trembling composure as Ali cracks spectacularly.
Writing
Chris Lang's script weaponizes domestic intimacy as dread.
Direction
Tight framing that turns every dinner table into interrogation room.
Trivia, insights & behind the scenes
This was Sarah Parish's first leading dramatic role after years of comedy, and she fought for the part after reading Lang's script in one sitting.
Sirens arrived in 2002 when British television was pivoting from cozy Inspector Morse-style mysteries to psychologically damaged protagonists — Ali Pearson is a direct ancestor of Happy Valley's Catherine Cawood.