Plenty of Hanna-Barbera cartoons have celebrity references, often in the voices and mannerisms of the characters. Yogi Bear is Art Carney, Doggy Daddy is Jimmy Durante, Top Cat is Phil Silvers, and so on. 1965's Secret Squirrel, however, took things to another level. The show is a light, kid-friendly parody of the James Bond films, with Secret Squirrel as Agent 000 of the Sneaky Service, taking his orders from Double-Q. Weirdly, however, there's also a film noir, Maltese Falcon aspect, with Secret Squirrel's sidekick Morocco Mole talking like Peter Lorre. The main antagonist, Yellow Pinkie, is obviously inspired by the titular villain from the 1964 Bond film Goldfinger, but he also resembles Kasper Gutman, the villain played by Sydney Greenstreet in The Maltese Falcon. The actual plots and animation from Secret Squirrel are generally pretty uninspired, so it's possible all these movie references were simply the result of its creators trying to keep themselves entertained, but it's definitely the most interesting aspect of the show.
