Jaws 3D famously contains one of the worst special effects ever featured in a major blockbuster, though an alternate version of this scene actually looked great; here's why it was scrapped. Despite franchises being a major part of the movie landscape now, they were fairly uncommon in the early 1980s. The success of 1978's Jaws 2 convinced Universal to produce another installment, but the original concept Jaws 3, People 0 was meant to be a parody of the series and Hollywood itself.

This idea was dropped in favor of a straight horror movie, with Jaws 3 being set in an aquatic park in Florida, where a 35-foot shark terrorizes the employees and guests. The movie was one of a cycle of movie sequels from this era that used 3D as a gimmick, including Friday The 13th Part 3. Unfortunately, the movie is a suspense-free slog, with most of the runtime revolving around the boring love lives of its lead characters or park politics. While it was a financial success, it received bad reviews and time has not been kind to its effects.

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One particular special effects scene from Jaws 3D has become somewhat infamous, which sees the shark very slowly swim into the glass of an underwater control room and cause it to flood. This shot looks terrible, from the barely mobile shark, the thick matte lines surrounding it and the fact it just stops when it hits the glass. There are several poorly realized effects throughout the movie, but in the case of this sequence, there was an alternate version produced that looked much more convincing.

jaws 3d origina shark glass smash effects

In the above image, the shark on the right is the shot that was used in the finished film, but the one on the left was the original version. The effects for Jaws 3D were mostly handled by a company called Private Stock Effects, who put together shots compositing on video instead of optical. This was a brand new method at the time and by all accounts, it was quicker and easier than using optical effects. That said, because of the lower resolution for video, the producer changed his mind and decided to replace most of PSE's electronic composite shots with hastily assembled opticals from another firm instead.

Most of PSE's effects work was thus thrown out, despite being described as far superior to the final product, with further unused shots being available to view at this Jaws 3D fansite. This includes the original version of the shark swimming towards the glass in Jaws 3D's finale, which looks far more natural and convincing, in addition to actually looking like it's underwater. The sequel itself had various issues during production, from the first week of footage being deemed unusable due to the 3D camera system used to the instance on using the Brody brothers as the protagonists to connect the movie to the first two.

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