Onarainynightin1928inaPennsylvaniafactorytowncalledIverstown,MarthaIvers(JanisWilson),thirteenyearsold,istryingtoescapefromtheguardianshipofherwealthy,domineeringaunt.Herfriend,thestreet-smart,poorSamMasterson(DarrylHickman),comesforherthroughherbedroomwindow,butMartha'sauntcatchesthem.WhileSamslipsoutunnoticed,MarthahitsMrs.Iversonthehead,causinghertofalldownthelongstaircaseanddie.ThoughSamsawnothing,theeventwaswitnessedbyWalterO'Neil(MickeyKuhn),thesonofMartha'stutor(RomanBohnen),knownasMr.O'Neil.MarthaliesabouttheincidenttoMr.O'Neil,andWaltersupportsher.[5]
Mr.O'NeilsuspectswhathappenedbutpresentsMartha'sversionofeventstothepolice,thatanintruderisresponsiblehemakesuseofhisknowledgebyhavinghermarryhisson.Whenthepoliceidentifyaformeremployeeoftheauntasthemurderer,thetwoO'NeilsandMarthahelpconvicthimheispunishedbyhanging.[5]
Eighteenyearslater,theolderO'Neilhasdied.Walter(nowplayedbyKirkDouglas)isthedistrictattorney,whileMartha(BarbaraStanwyck)hasusedherinheritancefromheraunttobuildalargebusinessempire.Theirmarriageisone-sidedhelovesher,butshedoesnotlovehim.
Sam(VanHeflin),nowadrifterandgambler,stopsinthesmalltownbychancetohavehiscarrepairedafteranaccident.Whilewaitingforrepairs,athisoldhome,nowaboardinghouse,hemeetsAntonia"Toni"Marachek(LizabethScott),whohasjustbeenreleasedfromjail.Sheislaterpickedupforviolatingherprobationbynotreturningtoherhometown.SamgoestoseeWalter,toseeifhecanusehisinfluencetogetherreleased.
WalterisconvincedSamhasreturnedwithblackmailinmind,givingWalteramotivetorunSamoutoftown.WhenMarthareactswithjoytothenewsofSam'sreturn,Walter'sjealousyprovidesanadditionalmotive.WalterforcesTonitosetSamup.Samisbeatenanddrivenoutoftown,butheistootoughtobeintimidated.Whenallelsefails,Waltermakesahalf-heartedattempttokillSamhimself,butiseasilydisarmed.Marthatheninadvertentlyblurtsoutthecouple'sfearsofblackmail,whichprovetobegroundless:Samsayshedidnotwitnessthedeath.Marthabreaksdownandlamentsthatheleftwithoutherallthoseyearsago,takingwithhimheronlychanceforloveandfreedom.
Samistornbetweenhisoldloveandhisnew.AlthoughheeventuallyforgivesToniforbetrayinghim,heandMarthaspendanidyllicdaytogether,rekindlinghisfeelingsforher.
WalterarrangestomeetSamtofinallysettlematters.BeforeSamarrives,WaltergetsdrunkandMarthafindsoutaboutthemeeting.WhenWalterfallsdownthestairsandisknockedunconscious,MarthaurgesSamtokillhim.SaminsteadbringsWalteraround.MarthapullsoutagunandthreatenstoshootSamin"selfdefense"asanintruder.However,SamgamblesthatWalterwillnotbackupherstoryheturnshisbackonherandleaves.
Walterembracesandkisseshiswifethenhepointsthegunathermidriff.Oddlyrelieved,sheputsherhandoverhishandonthetriggerandpresses.Assheisdying,shedefiantlystateshernameisnotMarthaIvers,butMarthaSmith.Outside,Samhearstheshot.Herunsbacktowardthemansion,butseesWalter,holdingMartha'sbody,shoothimself.SamandTonidriveawaytogether.