Christmas and Musicals seem to go hand in hand. So, it's no surprise that one of the most beloved Christmas movies of all time happens to tackle both. White Christmas, the Irving Berlin-created musical follow-up to Holiday Inn, is the crowning achievement of the Holiday Musical genre.

RELATED: 10 Things You Didn’t Know About The Making Of It’s A Wonderful Life

Starring icons such as Danny Kaye and Bing Crosby, the movie contains some of the flashiest choreography, catchiest songs, and most heartwarming moments of any Christmas film. It is a classic to be sure, but do you know everything behind the making of the film?

Class Clown

Though he played second fiddle to Bing Crosby in the film, Danny Kaye was front and center on the set of the movie. Throughout filming, Kaye brought his signature wit and humor to every scene, occasionally going a little overboard.

According to many actors and crew, Kaye was such a goof on the set that they had to end and toss takes because everyone kept cracking up from his jokes. Unlike today, too many retakes can cost the studio a lot of money if too much film was wasted. Luckily, Kaye's talent and personality made up for any lost film.

Finale Redux

The cast of the musical within White Christmas posing as they sing in red and white outfits

The finale of the film is a Christmas memory seared into the minds of all who watch it. It is one of the most iconic moments in any Christmas movie. It was so good that the crew had to do a repeat viewing after the supposed final cut.

It turns out, the King and Queen of Greece had been visiting the set and had missed the filming of the final scene. So, the director made them "reshoot" the scene without any film. Crosby, who was tired of filming at this point, skipped out on the show for the monarchs and went golfing instead.

First Vista Vision Film

White Christmas is more than just a time capsule due to its age. The technology used in the film was a bit of a rarity at the time, as well as today. It was the first film to utilize the new technology of VistaVision, a semi-gimmicky new way to capture the full scope of a picture.

RELATED: National Lampoon’s Christmas Vacation: 10 Facts Fans Didn't Know About The Holiday Movie

This technology allowed for higher resolution in the images by turning the 35 mm film in a horizontal direction. This resulted in a wider, more detailed version of the film. Though it wasn't as groundbreaking as the wall to wall Cinemascope, it's still a fun and retro footnote in the history of filmmaking.

Is That Alfalfa?

Long before The Avengers, there was an idea: bring together some of the most iconic Christmas movies into one shared universe. Ok. Maybe there wasn't, but that doesn't mean that there isn't some spillover between a ton of these movies.

In White Christmas, Phil and Bob head down to Florida to see the Haynes sisters perform. Mostly they do so since they served alongside the girls' brother. When Betty and Judy show them a recent picture you can see it is none other than Alfalfa himself, Carl Switzer. Switzer can also be found at the High School dance in It's A Wonderful Life.

The Former Holiday Inn

For many fans of classic musicals, you'll know that before White Christmas, Irving Berlin created another classic holiday musical alongside Bing Crosby: Holiday Inn. The movie focuses on Crosby who opens up a night club that is only open on major holidays.

It turns out the set that was assembled to create the Holiday Inn was actually foundational for White Christmas. The Columbia Inn is just the same remodeled set from the first film, changed to look like it is in the mountains of Vermont and not upstate New York.

The Sisters Number Was Unscripted

It turns out that some of the antics between Crosby and Kaye actually made it on to the screen. The iconic moment where the two don the Hayes Sisters' costumes and perform the Sisters number is one of the funniest and most memorable moments in the entire movie.

Apparently, the scene was never in the script. Director Michael Curtiz caught the two actors joking around on set and decided that it was so funny it had to be included in the final scene. The moment where Crosby begins laughing is his genuine reaction to the moment, not being able to combat the humor from Kaye.

Contrary Age Gaps

The movie has a lot of weird plot points surrounding age. The general played by Dean Jagger is grappling with aging, while Betty and Judy have an older sister/younger sister dynamic. Funnily enough, a lot of the actor's ages are contrary to these plot points.

Bing Crosby, who is meant to be much younger than the "old man" Dean Jagger, was actually a whole six months older than the actor. Rosemary Clooney, who played the older sister Betty, was actually seven years younger than Vera-Ellen, who played the younger sister Judy.

Shared Studio Effort

Nowadays, studios battle among each other over the rights to something as silly as Spider-Man. While they weren't best friends back in the day, at least they could occasionally share resources. For example, look at the train sequence in the film.

RELATED: 10 Best Christmas Musicals, Ranked

Paramount didn't have a train set at their studio, so they had to look elsewhere. The only other two studios in town that had one were 20th Century Fox and MGM. Paramount paired with Fox and utilized their stage for the sequences on the train cars.

Unscripted Snacks

Improvised scenes take a lot of well-working elements to pull off. The director needs to be willing to experiment, and the actors need to come up with a believable and fitting dialogue that matches the script.

Luckily, one really great scene fit the mark. In the film, Bob and Betty meet in the kitchen for a midnight snack. Apart from the song, the lead-up dialogue to this moment was entirely improvised by Crosby. His monologue on food and the nature of dreams was never in the script.

Miracle In Vermont

We might have been making up the Christmas Avengers, but this movie does contain a whole other Christmas movie cameo. In the film, Percy Helton appears as a train conductor who hounds Bob and Phil when they arrive without a ticket.

Helton also makes an appearance in the beloved film Miracle on 34th Street. In that movie, Helton plays the Santa Claus in Macy's Thanksgiving Day Parade who drinks a little too much to wet his whistle beforehand. While he is donning a long white beard in one film, Helton's iconic voice can still be recognized.

NEXT: 10 Things You Didn’t Know About The Making Of A Christmas Story