Alexander Harper Berkeley is an American actor. Since beginning his career in the early 1980s, he has appeared in over 200 film and television projects. His films include Terminator 2: Judgment Day (1991), Candyman (1992), Barb Wire (1996), Air Force One (1997), Gattaca (1997), and Shanghai Noon (2000). He also appeared in the crime dramas L.A. Takedown (1989) and its remake Heat (1995), although he played a different character in each film. On television, he headlined the Citytv psychological thriller The Booth at the End (2010–2012) and was a series regular on the Fox action drama 24 (2001–2003) and The CW action thriller Nikita (2010–2012). As a guest star, Berkeley portrayed Sheriff Thomas McAllister on the CBS drama The Mentalist (2008–2013) and Gregory on the AMC post-apocalyptic horror The Walking Dead (2016–2018).

Terminator 2: Judgment Day is a 1991 American science fiction action film directed by James Cameron, who co-wrote the script with William Wisher. Starring Arnold Schwarzenegger, Linda Hamilton, Robert Patrick, and Edward Furlong, it is the sequel to The Terminator (1984) and is the second installment in the Terminator franchise. In the film, the malevolent artificial intelligence Skynet sends a Terminator—a highly advanced killing machine—back in time to 1995 to kill the future leader of the human resistance John Connor, when he is a child. The resistance sends back a less advanced, reprogrammed Terminator to protect Connor and ensure the future of humanity.