Jay Leno in 'Mary Poppins Returns'? Why the former 'Tonight Show' host got 'special thanks' in the credits

Jay Leno played a part — albeit small — in the "Mary Poppins" remake.

No, the former "Tonight Show" host didn't actually appear in the movie. But one of his cars did happen to land a special role, according to Lin-Manuel Miranda, who plays a London lamplighter named Jack in "Mary Poppins Returns."

Fans were perplexed when Leno got a "special thanks" mention after the credits rolled past. They took to social media to dissect the film to determine how Leno was potentially involved. Eventually, after the topic was once again discussed on an episode of the podcast How Was Your Week With Julie Klausner, Miranda filled in the blanks.

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"Apparently, there is a car sound effect from the 1930’s that they could not replicate, and someone realized Jay Leno had the car they needed. To record the sound effect. There is your answer," Miranda explained in a tweet, adding that he was also previously confused by the nod.

Comedian Julie Klausner thanked Miranda for solving the mystery.

"Hello Lin, and thank you for this. The answer exceeds my imagination," she replied.

It's unclear which one of Leno's prized vehicles was used in the film. Leno, who hosts Jay Leno's Garage on CNBC, has a huge collection.

In May 2018, Leno told MSN Money he had about 181 cars and 160 motorcycles.

"I never set out to collect cars. I just bought what I liked. The general rule of car collecting is if you’re reasonably astute and you understand how things work, if you like it, chances are other people will like it, too," Leno explained to Money.

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He then explained his three rules before purchasing a vehicle — particularly an old one.

"It should be of technical and historical significance. It should be fun to drive. And it should be attractive to look at. If an automobile has those three qualifications, then it’s probably something that would be considered collectible," he added.

In January, nearly 15 days after it was released in theaters, Forbes reported "Mary Poppins Returns" passed $200 million worldwide.