In addition to Superman Returns, Harris and his writing partner Michael Dougherty have co-written many films, including Urban Legends: Bloody Mary and X2: X-Men United, which he wrote at the age of 22 for director Bryan Singer, an assignment offered to him after the director read the screenplay for Imaginary Heroes. In the same year, he was honored as one of Variety’s top 10 screenwriters to watch.
Harris is working on I, Lucifer, a film that Harris will be directing, based on the best-selling novel which he adapted with Michael Dougherty. Harris and Dougherty opted out of writing the upcoming Superman sequel expected to be released in 2010.
Also with Dougherty and Singer, Harris is writing a year’s worth of the Ultimate X-Men comic books for Marvel Comics and the Superman Returns prequel comic books for DC Comics. Recently, Harris’s photography has twice been published by New York fashion and arts landmark Visionaire and he was part of Vanity Fair’s "Hollywood Portfolio" in 2005.