Ross Fleming Butler (born 17 May 1990) is an American actor. He is best known for his role as Zach Dempsey in the Netflix series 13 Reasons Why and as Brett Willis on K.C. Undercover. He also played Reggie Mantle in the first season of The CW series Riverdale (2017). In 2019, he joined the DC Extended Universe as Superhero Eugene Choi in the film Shazam!, and reprised the role in Shazam! Fury of the Gods in 2023.