In the future, a race of 9-foot-tall, dreadlocked aliens called Psychlos takes over the earth following a nine-minute battle. A thousand year later, the few remaining humans are hunter-gatherers and the evil Psychlos maintain earth as an outpost for mining. Terl (John Travolta), furious at not being allowed to return to the home planet, decides to use humans to mine gold for him to keep. But one of the humans, Jonnie Goodboy Tyler (Barry Pepper), encourages the others to revolt.

There. Now you know everything you need to know about the movie and I’ve saved you the trouble of trying to sit through it. You might think it can’t be that bad because science fiction movies often have cheeseball dialogue and cardboard performances and as long as the special effects and explosions are good, it does not really matter. You would be wrong. This movie was made due to the ceaseless efforts of its star, John Travolta, and it is the most horrible example of vanity filmmaking since Isaac from “The Love Boat” cast himself as “Othello.”

The movie could be used as an exam for film school students on what not to do.

Acting: John Travolta’s performance as the bad guy in this movie is reminiscent not of his brilliant work in movies like “Get Shorty,” “Face/Off” and “Pulp Fiction” but of his character in “Welcome Back Kotter,” Vinnie Barbarino, trying to act tough. His attempts to sound imperious and sarcastic lack any sense of presence or dignity, and then, to make it worse, he follows them with an attempt at a contemptuous laugh that sounds a cross between Faye Dunaway railing about the wire hangers in “Mommy Dearest” and Dr. Evil in “Austin Powers.” Poor Forrest Whitaker does his best with an idiotic role as Terl’s sidekick and whipping boy. Some other actor struggles underneath the worst make-up job since Dan Ackroyd in “Nothing But Trouble.”

Design and effects: The humans look like a hair band on a bad day. The Psychlos look like a hair band on a really bad day. The sets are dark, dank, and uninspired. The explosions are boring. And it is all much too loud.

Dialogue: At some points, we hear the Psychlos’ dialogue as garbled mush resembling the way the clay people used to talk in the old “Flash Gordon” serials. Unfortunately, at times we hear it in English. “Couldn’t you forget to file the report, as a friend?” “As a friend I could forget to file the report, but fortunately, I’m not your friend.” “While you were still learning to spell your name, I was being trained in how to conquer galaxies!” “Never engage in a criminal activity unless you have a patsy to pin everything on.” And my personal favorite: “Jonnie, I know you don’t believe in fate, but I’ve always known this was your destiny.”

Plot: The plot is not very interesting and completely illogical. Even if we assume that the Psychlos really wanted minerals from the earth, if they were so advanced that they could annihilate the human population in nine minutes, how could it take them more than a thousand years to extract it? Jonnie has to figure out a way to produce gold for Terl while he and his men are really secretly using flight simulators somehow still functioning after a thousand years. This is to enable them to learn to fly fighter jets, also somehow still functioning after a thousand years, kind of like the scene in “Sleeper” when Woody Allen starts up a Volkswagen Bug that had been abandoned for hundreds of years, except not intentionally funny. The audience dissolved in laughter at Jonnie’s solution – just get the gold from Fort Knox, which conveniently had been overlooked during the Psychlo’s thousand-year domination of the planet, and was still intact but ready to be emptied out. Somehow a group of humans who are illiterate and have not even discovered the wheel manage to master thousands of years of literal rocket science in a couple of days, transport over to the Psychlos’ planet and blow it all up with one well-placed bomb. Not since that girl learned how to be a ballerina without leaving the house in “Flowers in the Attic” or Rock Hudson went to medical school really really fast so he could invent an operation to cure Jane Wyman’s blindness in “The Magnificent Obsession” has there been such an example of speed learning.

Halfway through the movie, my son leaned over to whisper, “It’s the movie Ed Wood wanted to make but never had the money for.” He is right – this movie has Wood’s genuine fervor overriding genuine ineptitude.

Parents should know that the movie has a lot of sci-fi violence, with lots of explosions, characters in peril and some gory dismemberment. There are a couple of mild expletives and some mild sexual references. Women are treated as sex objects or taken as hostages.

Families who see the movie should talk about the importance of learning and history (Jonnie is inspired by the Declaration of Independence), and they should contrast the way that the Psychlos use “leverage” (blackmail) to manipulate each other with the teamwork and loyalty shown by the humans. They might also want to compare this movie to some sci-fi classics, like the “Star Wars” movies. Or, they might just want to skip this one and watch those instead.