So far “The Staircase” makes the wearyingly popular true crime genre look easy. Colin Firth, left, and Toni Collette in a scene from the series “The Staircase.” There’s a big detour ...

Michael Peterson (Colin Firth) finds his life thrown into a frenzy when he discovers his wife Kathleen (Toni Collette) unconscious at the bottom of their stairs. She is later declared dead — and ...

The first three installments of HBO Max’s “The Staircase” are now streaming ... Kathleen Peterson (Toni Collette), a business executive married to novelist, columnist and aspiring politician ...