Olivieroisaburned-outwriter,livingathisestatenearVenice,hisdeadmotherdominatinghisimagination.Heisalsoadegenerate:sleepswithhismaidandhisex-student,hostsBacchanaliaforlocalhippies,andhumiliateshiswifeIrinainfrontofstrangers.Shelivesinterror.Whenayoungwomanismurdered,policesuspectOliviero.Thingsgetcomplicatedwhenhisyoung,beautiful,andself-confidentniece,Floriana,paysanunexpectedvisit.Asilver-hairedstrangerobserves.Morewomendie,andthoughtsofharmingIrinagiveOlivieronewinspiration.What'sFloriana'sgameandwho'stheobservantstranger?WatchingallisablackcatnamedSatan.