Theodore Peter James Kinnaird Taptiklis (born 16 December 1984) is a British actor and producer. He is of Greek and Scottish descent. He gained recognition for playing Tobias Eaton in The Divergent Series (2014–2016). He has starred in the horror films Underworld: Awakening (2012) and Underworld: Blood Wars (2016), the science fiction film Archive (2020), and the dark comedy The Monkey (2025) in a dual role as a pair of twin brothers. In television, James appeared in the short-lived CBS crime drama series Golden Boy (2013), the romance series The Time Traveler's Wife (2022), and the dark comedy series The White Lotus (2022), which earned him a nomination for a Primetime Emmy Award. Since 2024, he has played the lead role in Guy Ritchie's action comedy series The Gentlemen.