Inspired by haunting true events, The Bog tells the story of two couples, led by a troubled Collette (Parrish), who intertwined through friendship, unknowing infidelity and a tragic family death, decide to take an epic hiking trip into the remote Scottish Highlands to get away from it all, reconnect and stay at one of the secluded ancient cottages that dot the area. What starts as the time of their lives—and a much-needed, doctor-requested couples retreat—quickly spirals out of control for the group of friends in the isolated, harrowing mountain territory. There, they find themselves terrorized by unknown locals and unbeknownst to them, are subjected to a thousand-year-old mystical hunting ritual.