The Michael Keaton Batman Easter Egg You Missed In Charlie And The Chocolate Factory

Tim Burton's 2005 adaptation of Roald Dahl's "Charlie and the Chocolate Factory" is a strange contradiction. The film was pretty well-liked by critics when it was released, garnering an 83% approval rating on Rotten Tomatoes (based on 226 reviews), and it was popular with audiences, making almost $478 million at the box office. What's more, Willy Wonka costumes are still available in Halloween stores today, and Johnny Depp's look as the kooky chocolatier Willy Wonka has seeped into the popular consciousness. 

However, in 2026, one might be hard-pressed to find anyone who actually loves the movie. Many fans of Tim Burton agree that it's one of the director's lesser works, and most will admit that Mel Stuart's 1971 adaptation, "Willy Wonka & the Chocolate Factory," is the more memorable, vastly superior movie. Even Gene Wilder, the star of "Willy Wonka," hated it.

Burton's film stars Freddie Highmore as the titular Charlie Bucket, an impoverished, innocent moppet living in a strange, Dickensian version of England. He shares a tiny hovel with his parents and his four grandparents, the latter of whom never get out of bed. At the center of town is the mythic Wonka Chocolate Factory, which produces some of the most magical confections the world has seen.

Charlie's father is played by Noah Taylor, and at the beginning of the film, he is laid off from his job at the local toothpaste factory. There are a few scenes of Mr. Bucket standing by an assembly line, overseeing box after box of Smilex-brand toothpaste coming down the conveyor.

Fans of Burton's 1989 blockbuster "Batman," the one with Michael Keaton, will perk up at the word "Smilex," as "Smylex" was the name of the eerie chemical poison concocted by that film's villain, the Joker (Jack Nicholson). 

The fact that "Smilex" is used as the name of a toothpaste in "Charlie and the Chocolate Factory" is downright insidious. In "Batman," the Joker, formerly Jack Napier, was trained in chemistry and used his knowledge to develop a compound he called Smylex. When exposed to Smylex, a victim would have a prolonged laughing fit before falling down dead. The Smylex would also mutate victims to look like the Joker, causing their faces to stretch into unnatural grins. 

The insidious part was that the Joker, because he oversaw Gotham City's premiere chemical company, Axis Chemicals, was able to sneak Smylex into a wide variety of consumer goods, such as makeup, shampoo, underarm deodorant ... and possibly even toothpaste. Batman (Keaton) eventually discovers that Smylex activates only when several such products are combined, making it difficult to trace. The Joker also finds a way to convert Smylex into a gas and uses it multiple times throughout the film to poison people. In the finale of "Batman," the Joker fills hot air balloons with Smylex gas and uses them to poison an entire crowd. Jack Nicholson wanted the Joker to be scary, and that definitely clinched it.

The fact that Smilex-brand toothpaste exists in the world of "Charlie and the Chocolate Factory" implies that the film's own nearby citizens are being poisoned. Although, really, the toothpaste factory was merely used to denote that Mr. Bucket had a really boring job.

Of course, "Charlie" is such a kooky, stylized movie, and Willy Wonka such a bizarre character, that if the Joker had strode up to Mr. Wonka to shake his hand, it would have felt perfectly natural.