WhenoldfamilyfriendLouisaOxleyvisitsMissMarpleonestormynightseekinghelp,MissMarpledecidestosendherandherson,Archie,tosafetyatthelabyrinthineestateofGreenshaw'sFolly,ownedbyMissMarple'sgoodfriendKatherineGreenshaw,aneccentricbotanistandthelastsurvivingGreenshaw.LouisabecomesMissGreenshaw'ssecretary,andquicklyattractstheattentionofthegardenerAlfredPollockandactorNatFletcher.ThingsturnsinisterwhentheFolly'sfaithfulbutler,WalterCracken,iskilledinwhatappearstobeatragicaccident.Thenaguestatthehouse,HoraceBindler,disappearswithoutatrace.MissMarpleisconvincedallisunwell,andhersuspicionsareconfirmedwhenMissGreenshawherselfisbrutallymurdered.Suspectsareeverywhere,butnonecanimaginethesecrets,bothpastandpresent,whichMissMarpleuncovers.