Walter Brennan plays a dual role as D.J. Mulrooney, the kind-hearted lumber tycoon of Irish descent; and as the irascible 943-year-old gnome Knobby in the film, which has been described as "wavering between a comedy, a romance, a drama, and an environmental critique" The children, Elizabeth and Rodney, were played by Karen Dotrice and Matthew Garber, previously the Banks children in "Mary Poppins". Tom Lowell, who plays the young gnome Jasper in this movie, also appeared in the 1965 Disney film "That Darn Cat!" as Canoe, the befuddled surfer boyfriend of Hayley Mills.