Lefler was born in Southern California, and started making his first home movies at the age of twelve. He started in the film industry as an animator, having made short films as a child and then attended the California Institute of the Arts. His classmates included Tim Burton, John Lasseter, John Musker and Brad Bird. After two years, he worked for Disney and other studios for several years as a storyboard artist and animator, before progressing to directing. He worked for many years as a writer and storyboard artist on live-action features before getting his first chance to direct second unit on Sam Raimi's Army of Darkness in 1991.