Tim Sullivan attended John Bapst Regional High School in Bangor, Maine, the same institution that Tabitha Bruce, Stephen King's wife, graduated from. He then went on to earn a degree in literature from Florida Atlantic University.
After completing his education, Sullivan moved to southern California in 1988, where he resided for the next twelve years. During this time, he edited a horror anthology for Avon Books titled Tropical Chills, which was published in 1988. Additionally, he published his first novel, Destiny's End, also in 1988. This science fiction novel was followed by The Parasite War in 1989, The Martian Viking in 1991, and Lords of Creation in 1992. He also contributed to another horror anthology, Cold Shocks, which was published by Avon in 1991. Sullivan's literary output during this period was quite prolific, with numerous books being published throughout the early 1990s.
Sullivan's foray into the world of film began with his starring role in Somtow Sucharitkul's The Laughing Dead, released in 1989. In this charged performance, he played Father O'Sullivan, a character who becomes possessed by a Mayan god of death. Throughout the 1990s, Sullivan continued to work in film, scripting and acting in several micro-budget science fiction and horror movies, including Twilight of the Dogs, released in 1995, and Hollywood Mortuary, released in 2000. In the latter film, Sullivan played the role of actor-turned-zombie Pratt Borokov, a thinly disguised Boris Karloff.
In 2000, Sullivan left Hollywood and relocated to South Florida. In 2003, he moved in with librarian and science fiction critic Fiona Kelleghan in South Miami, Florida. During his time in South Florida, Sullivan continued to write fiction. He eventually left Florida in 2019, bringing an end to his nearly four-decade-long residence in the state.
