Karl's plays have been produced across the country and in New York. They include Greedy, FUBAR, Fair Game, Silverlake, North, Minneapolis, Dr.s F.s in the Terminal Ward, Big Sun Setting Fast, The Gilded Garden of Patcheww, Malibu, and Waco, Texas, Mon Amour. Screen work includes Pandora, The November Man, Shanghai, Higher, Widow's Walk, Reunion, The Next Best Thing (not the one with Madonna), The Condemned (co-authored) and Brother’s Blood (also co-authored). Karl worked as a Story Editor on the Showtime show Dead Like Me, creating 4 of the 2004 Season episodes. He also founded the script publication service, Big Sun Publication.