David Kenneth Harbour (born April 10, 1975) is an American actor. His accolades include a Screen Actors Guild Award and a Critics' Choice Television Award, in addition to nominations for two Primetime Emmy Awards, a Tony Award, and a Golden Globe Award.
He began his career acting in Shakespearean theatre productions. After his professional debut on Broadway in the 1999 revival of The Rainmaker, he was nominated for the Tony Award for Best Featured Actor in a Play for his performance in a production of Who's Afraid of Virginia Woolf?. He made his television debut on Law & Order in 1999 and had supporting roles in films such as Brokeback Mountain (2005), Revolutionary Road (2008) and Black Mass (2015).
Harbour gained global recognition for his portrayal of Jim Hopper in the Netflix science fiction series Stranger Things (2016–present), for which he received two nominations for the Primetime Emmy Award for Outstanding Supporting Actor in a Drama Series. His starring film roles include the title character in Hellboy (2019), Santa Claus in Violent Night (2022) and a former racer in the sports film Gran Turismo (2023). Harbour has played Red Guardian in the Marvel Cinematic Universe media franchise, beginning with the film Black Widow (2021), Thunderbolts* (2025) and in the upcoming movie Avengers: Doomsday (2026). Harbour has also joined the DC Universe as Eric Frankenstein, beginning with the television series Creature Commandos.