In the opening number, Willy Wonka drops a coin down a storm grate. In Willy Wonka e la fabbrica di cioccolato (1971), Charlie Bucket finds a coin in the storm drain which allows him to get his golden ticket so it may be a fan theory that the coin Charlie finds in the storm drain in the first film was the same one from this film.
Hugh Grant said director Paul King "sent me a mock-up of the Oompa Loompa stark naked. And my little children were a little alarmed at that." King added, "It was one of the most disturbing things I've ever seen in my life. If it ever leaks out, a generation of children will be scarred."
Wonka gets snagged by the innkeeper's fine print contract. Willy Wonka e la fabbrica di cioccolato (1971) has him prepare a large contract with fine print for the children to sign, which also becomes something that snags Charlie.
Director Paul King said he gained "about 50 pounds" from all the chocolate he ate on set, and added, "It's a miracle that Timothée Chalamet remains so slim and handsome." King explained, "We had this incredible chocolatier. She made these incredible concoctions, and we would taste them. They tasted much better than they needed to, because obviously, actors are good at pretending things, but the miracle was they tasted every bit as good as they looked."
When the Oompa-Loompa first introduces himself, he takes out what is clearly the same flute Wonka will use to summon the Oompa-Loompas in Willy Wonka e la fabbrica di cioccolato (1971), even playing the same melody.