AbigailClayton独自一人生活，已将近20年没有离开她的公寓。当她的邻居死亡，侦探FrankGiardello登门造访展开调查，她原本秩序井然的世界开始瓦解。AbigailClayton独自一人生活。一个人非常孤独。实际上，这位女继承人没有离开她的曼哈顿公寓已将近20年。当她年迈的邻居死亡促使纽约市警察局凶杀案侦探FrankGiardello登门造访展开调查，内心恐惧不安的AbigailClayton看到那位侦探在她门外，询问她。AbigailClayton曾试图收购现在空置的那个公寓以确保她的隐私，当新租户莉莲和查理搬进来时就更加烦恼了。AbigailClayton焦急地从她的前门的安全窥视孔监视她的新邻居，但当她终于面对面地遇到了莉莲和查理时她原本秩序井然的世界开始瓦解，她庇护的存在也开始成为意外和恐怖的方式威胁着。Anheiresswho’sbeenshutinsideherapartmentbuildingfornearlytwodecadesisforcedtoconfrontherfearsafteroneofherneighborsiskilledandadetectivearrivestobegintheinvestigation.AbigailClaytonlivesalone.Veryalone.Infact,theattractiveheiresshasnotleftherManhattanloftapartmentforalmosttwodecades.Thefamousdaughterofawealthyindustrialist,Abigaildisappearedfromthepryingeyesofthepressandtheintrusivenessofherfamilyonher18thbirthday,thedayshereceivedhermassiveinheritance.Duringyearsofself-imposedisolation,Abigailhashadcontactwithonlytwopeople-herbuilding’sConcierge,Klandermann,withwhomshecommunicatesvianotes-andDr.RaymondFontaine,alongtimefamilyfriendandhersoleconfidantformostofherlife.WhenthedeathofherelderlyneighborpromptsNYPDHomicideDetectiveFrankGiardellotolaunchaninvestigation,theagoraphobicAbigailisdistressedtofindhimoutsideherdoor,askingtoquestionher.Havingtriedtoacquirethedeadwoman’snowvacantapartmenttoensureherprivacy...AreclusiveManhattanheiressfindshercarefullystructuredworldbeginningtocrumbleafterherelderlyneighbordies,andayoungcouplemovesintothevacantapartment.Onher18thbirthday,AbigailClayton(SelmaBlair)receivedastaggeringinheritancefromherlatefather,anaffluentindustrialist.Thatsameday,Abigailalsoescapedtheprobinglensesofthepaparazzibysealingherselfawayfromtheworldinhermassiveloft.Nearlytwentyyearslater,theonlypeopleAbigailinteractswithareKlandermann(KevinPollak)theConcierge,andDr.RaymondFontaine(BeauBridges),atrustedfamilyfriend.Oneday,Abigail’selderlyneighbordiesundermysteriouscircumstances,andHomicideDetectiveFrankGiardello(GiovanniRibisi)comesknockingonAbigail’sdoorlookingforanswers.Concernedthattheopenapartmentcouldprovideaperfectperchforpryingeyes,Abigailinquiresaboutpurchasingittonoavail.Shortlythereafter,AbigailspiesCharlie(JasonLee)andLillian(AmySmart)movingintotheapartment.Intheweeksthatfollow,Abigailbeginsreligiouslyusingherpeepholetoscrutinizehernewneighbors’everymove.Butshecan’tstaylockedawayforever,andthemomentAbigailmeetsCharlieandLillianinperson,thenightmarebegins.AbigailClayton(SelmaBlair)livesalone.Veryalone.Infact,theheiresshasnotleftherManhattanapartmentforalmosttwodecades.WhenthedeathofherelderlyneighborpromptsNYPDHomicideDetectiveFrankGiardello(GiovanniRibisi)tolaunchaninvestigation,theagoraphobicAbigailisdistressedtofindhimoutsideherdoor,questioningher.Havingtriedtoacquirethenowvacantapartmenttoensureherprivacy,AbigailisfurtherupsetwhennewtenantsLillian(AmySmart)andCharlie(JasonLee)movein.Abigailanxiouslymonitorshernewneighborsfromthesafetyofherfrontdoor’speephole,butherwell-orderedworldbeginstounravelwhenshefinallyencountersLillianandCharlieface-to-faceandhershelteredexistencebecomesthreatenedinunexpectedandterrifyingways.