“Galaxy Quest” is a fanboy’s wet dream, and one hell of a movie concept. Its concept is so good I have to ask myself why no one has thought of it before. It’s just so perfect for a movie. We are asked this question: “What would happen if the cast of an old sci-fi TV show (say, ‘Star Trek’) suddenly became real-life versions of their characters?” The answer comes in the form of “Galaxy Quest,” which introduces the question then proceeds to answer it with great flair.

Tim Allen (TV’s “Home Improvement”) leads a stellar cast as Jason Nesmith, the egotistical actor of the movie’s fake TV show (think William Shatner, only with more hair). Nesmith is recruited by nonviolent aliens from another galaxy who have been receiving transmissions of Nesmith’s TV show and believes them to be actual “documentation” of Nesmith’s “journeys” across the stars. (The aliens don’t know what a TV show is, or even what a “lie” is).

While Nesmith, who has been feeling the pinch to his wallet as well as his ego, takes to being treated as a real space Captain with gusto, his stunned TV crew isn’t so sure. When it’s learned that the aliens have recruited Nesmith not just to run a real-life version of his TV starship, but also to face off against a scary lizard-like alien, things turn ugly. Can this group of fake space explorers battle a real villain? As one character states worriedly, “We’re actors, not astronauts!”

“Galaxy Quest” has a lot going for it. The special effects is quite good, even though in a movie that parodies TV sci-fi shows bad special effects wouldn’t have mattered a bit. In fact, if the effects had been laughable, or purposely bad, the movie could really have achieve a “cheese” factor by reminding people just how silly “Star Trek”’s effects were in its time.

What really makes the film work is its cast, including Sigourney Weaver as a not-too-bright blonde who is also Nesmith’s love interest on and off the show. Alan Rickman is a classically trained (and stuffy) British actor who plays a Spock-like character; Rickman hates that he’s constantly being upstaged by Nesmith during their reunions at sci-fi conventions. Another treat is the presence of Tony Shalhoub as Fred Kwan, the Scottie-like engineer who has a deadpan delivery and an attitude that makes one think Scottie might have been smoking something in Engineering whenever the Captain’s back was turned.

Another great character is Sam Rockwell as Guy, a “red shirt” character whose sole job on the show is to get killed off, and who is terrified of being killed for real once he realizes what he’s gotten into. (”Star Trek” popularized the notion of “Red Shirt” characters because, as fans like to point out, the first crewmate to get killed whenever the cast beams down to a planet is the unnamed guy in the red shirt.) Because he’s supposed to be killed off in every show, Guy’s character doesn’t even have a name! His paranoia at this status as the “red shirt guy” is pure gold.

It’s hard not to like “Galaxy Quest,” and anyone who has seen more than the occasional episode of “Star Trek” will have a blast and a half.

There is a moment early in the film when Nesmith is in a bathroom stall at a sci-fi convention and overhears fans ridiculing him and his inability to leave the TV show behind. This heartbreaking moment justifies our cheering for Nesmith when he’s finally given the chance to actually prove his worth as a “space captain.”

The above scene also makes me wonder how many times William Shatner has felt like that, since for every fan that adores Shatner, there’s probably one that snickers at the mention of his name. Tim Allen’s fictional Nesmith gets the chance to prove himself, but I doubt if real-life aliens will ever come down to Earth and ask Shatner for his help to battle a large lizard with an eye patch.

Then again…

Dean Parisot (director) / David Howard, Robert Gordon (screenplay)
CAST: Tim Allen …. Jason Nesmith
Sigourney Weaver …. Gwen DeMarco
Alan Rickman …. Alex
Tony Shalhoub …. Fred Kwan
Sam Rockwell …. Guy Fleegman
Daryl Mitchell …. Tommy Webber
Enrico Colantoni …. Mathesar