The Master is a fictional character on the action-horror/fantasy television series Buffy the Vampire Slayer (1997–2003). He is a centuries-old vampire portrayed by Mark Metcalf, determined to open the portal to hell below Sunnydale High School in the fictional town of Sunnydale where the main character Buffy Summers lives. The premise of the series is that Buffy is a Slayer, a teenage girl endowed with superhuman strength and other powers, which she uses to kill vampires and other evil beings. Each season of the series Buffy and the small group of family and friends who work with her, nicknamed the Scooby Gang, must defeat an evil force referred to as the Big Bad; the villain is usually trying to bring on an apocalypse. The Master is the first season's Big Bad.

Buffy the Vampire Slayer is an American supernatural drama television series created by writer and director Joss Whedon. The concept is based on the 1992 film, also written by Whedon, although they are separate and unrelated productions. Whedon served as executive producer and showrunner of the series under his production tag Mutant Enemy Productions. It premiered on March 10, 1997, on The WB and concluded on May 20, 2003, on UPN.