Sixpeopleboundtogetherbyatraumaticexperiencedecidetoroundoffayearofgrouptherapyinstyle.Theyjoineachotheroncemore,travelinguptotheScottishLowlandsforareunionweekendina1970sholidaylet.Soonanumberofmysteriousandhorrifyingeventsstarttoexposethecracksintheirrelationships,andonebyonetheydiscoverthattrustrunsbutskin-deep.Anightofclosureturnsouttobefarmorefinalthantheycouldhaveanticipated.