Dead Ringers (1988)

Dead Ringers is a 1988 Canadian-American psychological/body horror film starring Jeremy Irons in a dual roles as identiacl twin gynecologists David Cronenberg directed and co-wrote the screenplay with Norman Snider Their script was based on the lives of Stewart and Cyril Marcus and on the novel Twins ​by Bari Wood and Jack Geasland a highly fictionalized version of the Marcus story.

Plot
Elliot and Beverly Mantle are identical twins and gynaecology who jointly operate a highly successful clinical practice in Toronto that specializes in the treatment of female fertility problems Elliot the more confidente and cynical of the two seduces women who come to the Mantle Clinic When he tires of them the women are passed on to the shy and passive Beverly whlie the women remain unaware of the substitution.