The Sinner (Seasons 1–4)

The Sinner (2017) is a crime anthology drama you can watch online on iFILM. On a crowded beach, young mother Cora Tannetti pulls a knife and stabs a stranger to death in front of everyone. She can't say why she did it. Neither can anyone else.

There's no mystery about who held the knife. The puzzle is the motive — what flips a quiet, law-abiding woman into a killer in broad daylight. Detective Harry Ambrose, played by Bill Pullman, digs through Cora's buried memories to find out, fighting his own wreckage along the way. Jessica Biel anchors the first season as Cora and produced it too.

Creator Derek Simonds built each season as a fresh Ambrose case, chasing the "why" instead of the "who" — closer to a psychological thriller than a whodunit. The opening season draws on Petra Hammesfahr's novel. If you prefer slow, character-deep stories about damaged minds over shootouts and chases, this one's for you. Stream every season of The Sinner online on iFILM.