Troubledbyboutsofsleepwalkinganddisturbingnightmares,graduatestudentSarahFostergoestoheruniversitysleepresearchcenterforhelp.Butwhenshewakesupafterherfirstnightofbeingmonitored,theworldshelivesinseemstohavechangedinsubtle,Twilight-Zone-esqueways.

Troubledbyboutsofsleepwalkinganddisturbingnightmares,graduatestudentSarahFostergoestoheruniversitysleepresearchcenterforhelp.Butwhenshewakesupafterherfirstnightofbeingmonitored,theworldshelivesinseemstohavechangedinsubtle,Twilight-Zone-esqueways.

Sarah'ssleepwalkingworsensasshegrievesherdaughter'sdeathinacarcrashthatleftherabusivehusbandcomatose.Shestrugglestodistinguishrealityfromnightmareasvisionsofhimhaunttheirhome.