Windlesham is a non-canonical character created for the 2022 Kenneth Branagh adaptation of Death on the Nile. He is a doctor and a member of Linnet Doyle's wedding party and later a passenger on the Karnak. Like the others, he also has a backstory which links him to Linnet and a plausible motive.
Windlesham shares some of the backstory of Charles Windlesham from the original novel in that he had also once proposed to Linnet. According to Bouc, "He and the papers both had the deal as good as done" but Linnet broke off the engagement. Windlesham also has some of the characteristics of Mr Ferguson in that he is a lord but does not use his title. However he is not an out-and-out socialist like Ferguson, although he is committed to serving humanity. Finally Windlesham parallels the role of Carl Bessner in that he is the only doctor on board the Karnak.
At the end of the film, Windlesham tells Poirot that he is not returning to London. He is planning to go to West Africa where he can use his medical skills to serve the people there.
Windlesham is portrayed by Russell Brand.