Lee is a New York Times best-selling artist, best known for his work on Batman, Lucifer and Batgirl for DC and Spider-Man, Loki: Agent of Asgard and Defenders for Marvel Comics. Lee has produced concept design and promotional imagery for several movies, including X-Men: Days of Future Past and Mile 22 and worked on various ad campaigns and poster designs for the likes of Lucasfilm, Warner Bros and The Jim Henson Company.