Filmmaking is a very long and complicated process, and the version of a movie that ends up in theaters is usually the result of a considerable amount of trimming. Before studios get anywhere near to a theatrical cut, they director starts out with a version of the film referred to as the "assembly cut."

Extended cuts of movies are often used as a marketing tool to attract fans by offering expanded material that was initially cut from the theatrical cut. Director's cuts have also been making the rounds in recent decades, offering a specially edited version of the film tailored to the director's personal vision rather than crowd-pleasing and studio demands. However, the lesser-known cut during the editing stage is the assembly cut and that's simply because this version is generally far too long to ever be released.

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Once a movie wraps filming, it heads into the post-production stage which lasts months or even more than a year depending on the amount of VFX work required. The director and editor of the movie begin the editing process by laying out every scene that's been shot in the correct sequence to create the assembly cut. The assembly cut, however, is not releasable footage and could be more than double the length of the finished product. This version then developed and cut down for pacing, length and storytelling reasons until it's eventually transformed into the theatrical cut of the movie.

An Assembly Cut Is NOT A Director's Cut

Justice League Zack Snyder Cut

Just because extended cuts and director's cuts of movies are lengthier, it doesn't mean that they're the same as the assembly cut. Much work has to be done following the assembly cut in order to transform footage into a releasable product. The assembly cut is a rough draft that the creative team needs to keep reworking through the footage. To develop a director's cut, directors usually take a deeply edited version of the movie, well after the assembly cut stage, and put their own representation before other eyes make the final cut.

With the buzz surrounding Zack Snyder's director's cut of Justice League, DC fans have been hellbent on getting a fuller version of the 2017 movie. The public has debated whether the "Snyder Cut" existed, but the director has since confirmed that it's real. The theatrical version of the film of the movie came in at two hours, and while confirming the existence of the Snyder Cut, Snyder also revealed that the version is over three hours long. When questioned about whether he was referring to an assembly cut of Justice League, he took to Twitter to clarify that the assembly cut was close to five hours long. It's still unclear if the Snyder Cut will ever be released, but it's important to remember that just because different versions of a film exits, they might not necessarily make the movie better.

Next: Justice League: Snyder Cut Has Better CGI Than the Theatrical