GovernmentmathematicianChrisBartonlivesaroutinelife—until,attheendofanordinaryworkday,hefindshiscarmissingfromtheemployeeparkinglot.Whenhefinallyarriveshome,thereisastrangerlivinginhishouse—amanwhoclaimstobehim.Thrustsuddenlyintoasurrealworldwheretheevidenceofhissensescannotbetrustedandstrangersaretryingtokillhim,Chrismustavoidviolentassassinswhilefollowingatrailofcrypticcluestoregainhislife.