Why is Patton Oswalt in this Movie?

When this movie was made, he was a completely nondescript actor. He was just a filler crewman on the sub. If he didn't become more famous, no one would have even noticed his part in the movie. Watch the film again. There are several superfluous actors portraying crewmen of one sort or another. Look at the last scene. There are forty some actors portrayed as crewman of the Stingray. But we only see about a dozen during the entirety of the film. Oswalt could have just as easily portrayed the Admiral's driver, or any one of the dozens of people who were on camera on the Orlando without a specific purpose. Sorry I've ranted on this but when all is said and done, in all likelihood, you would probably never even have noticed Oswalt if his career didn't give him more exposure subsequent to this film.

Harry Dean Stanton was also barely in the movie. It was like they were paying him by the minute.

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I'm just expressing my opinion.

You may all go to hell, and I will go to Texas.

He actually had to leave filming about two weeks early to take a job as a staff writer for MadTV

Well I would assume because he auditioned for a part, probably had some bills to pay ya know that sorta thing.

I don't even remember him having a single line. He just sat behind the foreground action, looking grave.