Robert Heinlein's "Puppet Masters" is a classic chunk of sci-fi... so inevitably it got semi-mauled by the movie industry.
And the movie adaptation is sort of a half-and-half affair. Stuart Orme manages to maintain an intelligent, genuinely creepy atmosphere throughout the first half of the movie, only to spend the second half gleefully throwing in lots of gun battles, chases and really atrocious acting by Eric Thal.
Government agency head Andrew Nivens (Donald Sutherland), his agent son Sam (Thal) and NASA exobiologist Mary Sefton (Julie Warner) arrive in a small Iowa town to investigate a UFO hoax.
But they soon learn that it's no hoax -- the town has been infected by body-snatching alien manta rays (which would make an awesome band name), and they accidentally bring one back to Washington. The aliens are spreading through Iowa and Washington, they're strong nd smart, and there's almost no way of getting one off without the host dying.
And to make matters worse, Sam is even briefly infected with one, which almost leads to the president being possessed. With only a matter of days before the entire Earth is overrun, Our Hero leads a special military team to.... rescue his love interest. Oh yeah, and maybe save the world while they're at it, if he stumbles across the solution.
"The Puppet Masters" is a true classic -- it spawned "Invasion of the Body Snatchers," "The Faculty" and even a "Star Trek" episode. It's a pretty intelligent look at the societal changes that might come from alien parasites, and "The Puppet Masters" sticks to that for quite some time.
In fact, the first two-thirds of the movie are a pretty faithful adaptation of Heinlein's novel, with plenty of haunting suspense and scientific exploration. It's an atmosphere where nobody can be trusted, and anyone who attempts to stop the aliens will become their new slaves. There are some truly harrowing glimpses of what the aliens do to people, and creepy moments galore (such as the "Do you miss me?" message from a posessed chimp).
Unfortunately about halfway through, Stuart Orme decides to throw in a cliche damsel-in-distress story, with the required gun battles and airborne wrestling matches. And it's riddled with fairly obvious plot-holes (why don't people go shirtless to show they're not possessed?) that leave you wondering how such stupid people got into uber-powerful government agencies.
And the cast is a very mixed bag -- Donald Sutherland is simply brilliant as Niven, exuding a sort of stern paternal feel, while being willing to do whatever it takes to save the world. We never find out why his son loathes him, though. Warner does a decent job despite being nothing more than the Required Love Interest for the main character, and Keith Warner is quite good as Sam's military sidekick.
Eric Thal is a total disappointment, though. His acting is embarrassingly bad in any scene that requires major emotion -- which he usually conveys by twitching and opening his mouth. He seems to have been hired mainly for his oft-displayed hot body, including the worst post-trauma shower scene I've ever suffered through. Seriously, it's basically an excuse for Thal to slither around naked on the tiles.
"The Puppet Masters" starts and proceeds as a smart, eerie sci-fi thriller, but starts deteriorating into another dumb Hollywood blockbuster by the last lap. At least Sutherland keeps things worthwhile.