Unfortunately for Felix, Oliver has been manipulating their entire friendship from the very start. After seeing Felix on campus at Oxford surrounded by adoring friends, Oliver sabotages Felix’s bike so the popular boy has to borrow one from Oliver. Beyond that, Oliver completely fabricates the details of his life; despite him telling Felix that he’s desperately poor and the son of a deceased father and an alcoholic mother, not a word of it is true.
Felix believes every word of Oliver’s story until, trying to be kind, he drives Oliver to the Quick family house to help him make amends with his troubled mother after his father’s “death” … but not only is Oliver’s father alive, but Paula and Jeff Quick (Dorothy Atkinson and Shaun Dooley) are nice, kind people with nothing but praise for their accomplished son.
Felix is understandably disgusted by Oliver’s deceit, telling the non-Catton that he’ll have to leave Saltburn immediately after his birthday party. During the party, Oliver repeatedly attempts to make amends with Felix, who’s completely uninterested and simply wants Oliver to leave his life. Much later in the film, Oliver reveals — to both the audience and Felix’s mother, Lady Elspeth, played by Rosamund Pike — that he laced Felix’s drink with drugs, making it look like his death was an overdose. Why? Oliver is obsessed with Felix, who rejects him; if Oliver can’t have Felix for himself, then he has to kill him.
