Randolph Severn "Trey" Parker III (born October 19, 1969) is an American actor, animator, screenwriter, director, producer, comedian, and singer-songwriter. He is best known for being the co-creator of South Park along with his creative partner and best friend Matt Stone, as well as co-writing and co-directing the 2011 musical The Book of Mormon. Parker grew up in Conifer, Colorado and was interested in film and music growing up. He attended the University of Colorado, Boulder following high school, where he met Stone. The two collaborated on various short films, and starred in a feature-length musical, titled Cannibal! The Musical, in 1993.

The duo moved to Los Angeles and later premiered South Park on Comedy Central in August 1997. The duo, who possess full creative control of the program, have since produced a feature film, music and video games based on the show, which continues to run. Alongside Stone, he has also produced various feature films and television series, among those Team America: World Police (2004), a political satire starring marionettes. After several years of development, The Book of Mormon, a musical co-written by Parker, Stone, and composer Robert Lopez, premiered on Broadway and has since become immensely successful. In 2013, he and Stone established their own production studio, Important Studios.