So, it's basically 3 Amigos...

Now that you mention it.

It's also a better Star Trek than any of the theatricals except maybe Save the Whales.

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Guacamole in my choos

The big difference being this movie is funny. Three Amigos wasn't.

Tonight or i will kill her

You did it incorrectly. It's supposed to be: ...IN SPACE!!!!!!!!!!

"I don't want a bloody avatar!" -paraphrased from BQQ's annoyances with IMDb's stupidity

Sort-of.

They do have similar set-ups, but Three Amigos and Galaxy Quest are very different beasts.

And I do honestly believe that Galaxy Quest is a much stronger film that holds up a lot more, especially on repeated viewings over time. It's one of those movies... It's been out 17 years, and I've watched it at least a few times every single year since it's come out. It never stops entertaining and never stops charming you, and you never stop loving it, no matter how many times you see it.

And FURTHERMORE, this is my signature! SERIOUSLY! Did you think I was still talking about my point?

Good night Ned

Add Tropic Thunder to the list of films with a similar theme where actors are put into a situation to play out their characters because someone thinks their characters are real.

I think there was even a nod to three amigos with this line:

"As long as there is injustice, whenever a Targathian baby cries out, wherever a distress signal sounds among the stars, we'll be there."

I guess they're both sort of references to Tom Joad's famous speech in The Grapes of Wrath though.