Plenty of movies have hidden Easter eggs, secret clues, and hints at projects both past and future. Though Disney has long been the forerunner in terms of hiding tidbits in their films, Pixar has some tricks up its sleeve, as well.

Apparently, one of those tricks is a secret "good luck charm" that's been hanging around Pixar since the '90s. But more on that in a minute.

First, let's be honest: Pixar hasn't had wild success with every film, despite their "good luck charm." So clearly, there's no precise magic formula for creating a hit movie. In fact, 'The Good Dinosaur' is widely known as Pixar's "first" flop.

But in most of the studio's movies, there's one common thread that helps make it spectacular, says IMDb. And it all started in 1995 with 'Toy Story.'

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IMDb trivia suggests that Pixar is the only animation studio to have one specific voice actor in every one of its projects. While a fairly long list of actors has voiced more than one Disney/Pixar character, none can say they've been in every film — except one.

The actor who voiced Hamm, John Ratzenberger, is the studio's golden ticket, says IMDb. His appearances in every post-'Toy Story' animated film makes Pixar the only studio to have a specific voice actor recurring in each project.

The voice actor, who is now 73, has had roles in Pixar's first 22 films, but the 23rd (Pixar) departed from tradition a smidge. He started out as Hamm, of course, and voiced the piggie bank in all four of the 'Toy Story' movies.

Juan Ortodoncia in 'Coco' - Unnamed cameo in 'Soul' - Mack in 'Cars'
via Disney Wiki/Laughing Place

He was the flea in 'A Bug's Life,' voiced the Abominable Snowman in the 'Monsters, Inc.' films, played an entire school of Moonfish in 'Finding Nemo' (he was a crab in 'Finding Dory'), and portrayed The Underminer in 'The Incredibles' (both the first and second).

But he also voiced Mack the semi-truck in the 'Cars' series, and in an amusing twist, had a specific scene where Mack himself realizes that Ratzenberger is, in fact, the voice behind all his favorite characters in a range of (car-themed) Pixar movies. Talk about introspection!

Ratzenberger's other roles are a bit tougher to catch while watching movies like 'Ratatouille,' 'Up,' 'Brave,' 'Inside Out,' 'The Good Dinosaur,' 'Coco,' and 'Onward' — but he's definitely there!

The one film that broke trend for the actor was 'Soul,' in which Ratzenberger doesn't voice a character, but is in fact illustrated into a scene. He was a non-speaking background character, but that does mean he was "in" the movie. Which could explain why so far, despite some critical interpretations of the main character's devolving from being a live human, the film was a hit.

Sounds like a pretty good lucky streak for Pixar, and it just might be because John participated in every movie.

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