If it's crap ... We'll tell you
Mars Attacks is a very fun movie, starting out pretty slow but building into an enjoyable climax. It's silly and nostalgic, but most of all it doesn't take itself seriously for a moment and that's what really works about it.
After the government confirms life on Mars, the martians decide to land on Earth in an all-out invasion, killing anybody who gets in their way or looks at them funny. It has an all-star cast including Glenn Close, Annette Bening, Pierce Brosnan, Danny DeVito, Martin Short, Sarah Jessica Parker, Jack Black, Michael J. Fox, Natalie Portman, Tom Jones and Jack Nicholson in duel roles as the President of the United States as well as a hotel tycoon in Vegas.
I think what I really love about this movie, as stands to reason, are the aliens. Their physical designs are disturbing and able to create genuine tension just from looking at them. They use multiple weapons throughout the film and each of them as a very unique kill that's fun to discover. But what's really great about them is that they aren't out for any sort of revenge and they aren't even really looking to take over Earth as a main goal. Basically they're just jerks who want to screw with people and have a good time. They see humans as pathetic weak idiots and the humans don't really have an argument in their defense. The aliens spend most of their time laughing at their own jokes and our futile attempts to stop them. It's pretty funny and you get to a point early on where you actually just want to root for the martians.
The movie is akin to the sci-fi films of the 50s and 60s, with each character playing an archetype from the genre to its n-th extreme. Brosnan plays the scientist who just wants to study the aliens and eventually develops a romantic interest. Then you've got Rod Steiger as the crazy, war-mongering general who just wants to blast the aliens out of the sky. It all works really well as an homage and self-parody of the nostalgia that comes along with those films. What's more is it completely contrasts the aliens who are unique and make things difficult for the archetypes to understand. The movie gets chaotic in the best way and the payoff is so ridiculous that it works perfectly. Also, the score is just as equally pleasing an nostalgic. It's one of my favorites of all time.