Theo James (born Theodore Peter James Kinnaird Taptiklis, 16 December 1984, in High Wycombe, England) is an English actor and producer best known for his breakout role as Tobias "Four" Eaton in The Divergent Series (2014–2016), where he performed his own stunts. He made his screen debut in a 2010 episode of Downton Abbey and appeared in the Underworld films Awakening (2012) and Blood Wars (2016). On television, he earned a Primetime Emmy nomination for his role in the acclaimed dark comedy The White Lotus (2022), starred in The Time Traveler's Wife (2022), and has led Guy Ritchie's The Gentlemen since 2024. He also executive produced and starred in the Jane Austen adaptation Sanditon (2019), the sci-fi film Archive (2020), and played twin brothers in the horror-comedy The Monkey (2025). A philosophy graduate from the University of Nottingham, he trained at the Bristol Old Vic Theatre School before being named a "Star of Tomorrow" by Screen International in 2009.