A scientist (Richard Hatch) who experiments on lab animals is given a meteorite fragment that contains an alien life form. Unknown to him, it crawls inside his body while he's asleep and due to some interesting scientific stuff, the man becomes pregnant. Although his boss and the Feds want to destroy his offspring, he sees it as his legitimate son and fights to protect it.
There's plenty of cheesy acting from a variety of notable sci-fi faces. At least one character from each "Star Trek" series is in this movie (I dare you to recognize them all). The plot is a bit flaky, and you can question how a man can give birth (they do attempt to explain this). The special effects are good at times, odd at others. The whole Charlie Chaplin thing is pretty weird.
What will disappoint many people is that half of this film is more of a courtroom drama than a science fiction film. There's an alien and all that, but the real focus of the film is debating what is or is not human and whether it has rights or not. Some of the arguments are preposterous and while they hold up in this film would never hold up in real life. The attempt to compare aliens to minorities is weak, ignoring the fact that foreigners are not given the rights of American citizens, and neither are animals. The only chance they can make their case is if they successfully have Ben (the alien) declared the naturally-born son of the main character, which is a stretch.
There's some parallel here to Larry Cohen's "It's Alive", although I'm sure this was not intentional. In that film (or one of its sequels), a father fights for his son's life in court despite most people thinking the kid to be a monster, as his DNA was radically altered by chemicals. That case would be a little easier to make, ignoring the alien aspects and the born from a man thing...
I enjoyed "Inalienable". Do I think it was amazing? No, not really. But it's not bad and worth a watch if you're into science fiction. The writers really put in a serious effort to make this sound plausible, though they clearly don't know how the law works. If you watch SyFy channel movies, which is where you're likely to see this if you don't rent it, this is better than most of the fluff they show.
Review by gavin6942 from the Internet Movie Database.