Sullivan is a graduate of the University of Southern California Film Writing School, where he also taught as an adjunct professor of screenwriting.
Sullivan began his writing career with the daytime dramas As the World Turns and One Life to Live, before transitioning into directing and producing with the Off-Broadway comedy productions of "What If We Did This?"
He directed and edited commercials, documentaries and new media campaigns for various companies, including ABC Network, Pollinator Press, Saab and Holiday Inn Express.
In 2007, he co-wrote, edited and produced the independent family comedy I'll Believe You starring David Alan Basche, Patrick Warburton and Chris Elliott.
He wrote for Law & Order: Criminal Intent, starring Jeff Goldblum and Saffron Burrows, Rizzoli & Isles with Angie Harmon and Sasha Alexander, and Supergirl.Sullivan's other writing credits include ABC's Revenge, starring Emily VanCamp and Madeleine Stowe and the Marvel Graphic Novel Revenge: The Secret Origin of Emily Thorne.