Today we remember Chuck Jones, the man who helped create so many great Looney Tunes’ cartoons. | Looney Tunes

The 1966 animated special was a collaboration between director Chuck Jones and author Dr. Seuss, who had previously worked together on World War II training cartoons. Jones approached a reluctant Dr. Seuss about adapting the book, and after a collaborative two-month process of storyboarding (real production cels featured in this video), they sold the special to a sponsor. Jones’s direction and the creative team’s attention to detail, including using Boris Karloff for narration and the Grinch’s v