He is best known for his roles in the Kingsman film franchise and in the television series Wolf Hall (2015), London Spy (2015), Alias Grace (2017), and The English Game (2020).
[3] He initially wanted to become a professional drummer, having attended music school, but switched to acting after appearing in a play at Oxford Brookes University.
[4] Holcroft is best known for his roles as Charlie Hesketh in the 2015 film Kingsman: The Secret Service and its 2017 sequel Kingsman: The Golden Circle; as George Boleyn in the 2015 British drama series Wolf Hall;[5] and as Alex Turner in the 2015 BBC drama series London Spy.
[6] In 2015, Holcroft acted with Dominic West and Janet McTeer in Les Liaisons Dangereuses at the Donmar Warehouse.
[7] In 2017, he appeared in the historical miniseries Gunpowder on the BBC and Alias Grace on Netflix and the CBC.