Mark Verheiden is an American television, movie, and comic-book writer. He was a co-executive producer for the television series Falling Skies for DreamWorks Television and the TNT network. Verheiden's introduction into writing comics came in June 1987, when he penned The American, which was published by Dark Horse Comics. Starting in March of the following year, he wrote what was to be the first of many Verheiden/Dark Horse comics based on the 20th Century Fox film-series Aliens, and comics based on the similarly licensed property Predator soon followed. He contributed to the1989 Harvey and Eisner A1 anthology series. his Phantom stories featured in a 13-issue maxi-series from DC Comics Verheiden contributed to scripts for the feature films The Mask and Timecop, both based on Dark Horse comics, and the latter based on Verheiden's creation. Verheiden was also the creator/writer and supervising producer on the ABC television series Timecop. Verheiden was a writer and executive producer on NBC's short-lived 2014-15 series Constantine based on the Vertigo/DC Hellblazer comic.