Murray Head plays artist Bob Elkin
Sunday Bloody Sunday on IMDB
'A Jewish doctor, Daniel Hirsh (Finch) and a young woman, Alex Greville (Jackson) are both involved in a love triangle with the same person, artist Bob Elkin (Head). Not only are Hirsh and Greville aware that Elkin is seeing the other, but they know each other through mutual friends. Despite this, they are willing to put up with the situation through fear of losing Elkin, who switches freely between them.'
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