Zak Penn's career in the film industry began when he sold his first screenplay, Last Action Hero, at the tender age of twenty-three. This marked the start of a long and illustrious career, during which Penn would go on to make a significant impact in the world of Marvel comics. He wrote scripts for numerous films based on these iconic characters, including X-Men 2 and X-Men: The Last Stand, The Incredible Hulk, and The Avengers. In addition to his work on Marvel properties, Penn has also dabbled in other genres, penning scripts for a diverse range of films such as P.C.U., Behind Enemy Lines, and Suspect Zero.
Penn's foray into independent cinema began when he collaborated with his idol, the renowned filmmaker Werner Herzog, on the script for Rescue Dawn. He went on to direct and co-star with Herzog in Incident at Loch Ness, a critically acclaimed "hoax" documentary that explored the legendary director's attempts to make a film about the mythical monster of Loch Ness. The Grand, Penn's second completely improvised film, was his third collaboration with Herzog, and featured an eclectic cast that included Woody Harrelson, David Cross, Ray Romano, Cheryl Hines, Dennis Farina, and Gabe Kaplan.
In addition to his work in film, Penn has also made significant contributions to the world of animation. He co-wrote the original story for Antz and produced the animated film Osmosis Jones. His first foray into television was the critically acclaimed SyFy Channel original series "Alphas," which starred the esteemed actor David Strathairn. Most recently, Penn was involved in the production of the video game documentary Atari: Game Over, which premiered on Xbox Live.