A graduate of the Royal Academy of Dramatic Art, he is known for his starring role as a fictionalized King George III in the Netflix period drama miniseries Queen Charlotte: A Bridgerton Story (2023).
[5] Upon graduating from RADA, Mylchreest was cast in open-air productions of the Shakespeare plays Romeo & Juliet and A Midsummer Night's Dream directed by Abbey Wood.
[6] Also in 2022, it was announced Mylchreest would star as a young, fictionalised version of King George III in the period drama prequel miniseries Queen Charlotte: A Bridgerton Story, which was released on Netflix in May 2023.
[7][8] Karama Horne of TheWrap was appreciative of the chemistry between Mylchreest and India Amarteifio (who played the title role of Queen Charlotte) and added that he "does a beautiful job wandering through the wilderness of King George’s mind without being campy".
[10] He made his West End debut as Edmund in Kenneth Branagh's production of King Lear at Wyndham's Theatre.