The show was conceived by Bob Keeshan, who also played the title character "Captain Kangaroo", and who based the show on "the warm relationship between grandparents and children". Keeshan had portrayed the original Clarabell the Clown on NBC's "The Howdy Doody Show" during its early years. "Captain Kangaroo" had a loose structure, built around life in the "Treasure House" where the Captain (the name "kangaroo" came from the big pockets in his coat) would tell stories, meet guests, and indulge in silly stunts with regular characters, both humans and puppets. Keeshan performed as the Captain more than 9,000 times over the nearly 30-year run of the show.