Michael Crichton

Michael Crichton was a doctor who wrote speculative fiction (S.F.) novels, many of which were translated into successful movies such as the Jurassic Park series.

The Andromeda Strain | book | movie | TV mini-series

In the Andromeda Strain the plot may seem to be an old sci-fi standby:
"Earth is invaded by Aliens and our four heroes save the day".
... but believe, me there's a twist or two in this telling!
For a start the Aliens aren't 7 feet tall, they don't have acid blood, lasers or spacecraft, and the heroes aren't centrefold models.
In fact, our heroes are middle aged - not too attractive - and their only super power is ... the mind! Not even psychic power - no - just good old fashioned intellect, rational thinking and scientific method.

The movie was made in 1971, based on Michael Crichton's (first) novel of the same name.
I didn't see it until 1997, and I've watched it several times since. I stumbled across it late one night on cable and was enthralled and amazed.
Enthralled because of the way the mystery invader is attacked with brains rather than brawn and amazed along the lines of - "this would never be made today!". Those who think Blade Runner is a thinking person's movie should see this!

Geek Factor: The huge underground lab is filled with computers - it takes you back to the days of low res mono displays. Four scientists talking science. That's unusual enough in itself (in Hollywood).

From www.crichton-official.com/strain/index.phpl:
" Previous to Stone's paper, most discussion of contamination dealt with the hazards to other planets of satellites and probes inadvertently carrying earth organisms. This problem was considered early in the American space effort; by 1959, NASA had set strict regulations for sterilization of earth-origin probes.

The object of these regulations was to prevent contamination of other worlds. Clearly, if a probe were being sent to Mars or Venus to search for new life forms, it would defeat the purpose of the experiment for the probe to carry earth bacteria with it.
Stone considered the reverse situation. He stated that it was equally possible for extraterrestrial organisms to contaminate the earth via space probes. He noted that spacecraft that had burned up in reentry presented no problem, but "live" returns - manned flights, and probes such as the Scoop satellites - were another matter entirely. Here, he said, the question of contamination was very great.
" At the lowest level of this laboratory is an automatic atomic self-destruct device," Stone said.
"It is controlled from within the laboratory. I have just inserted my key and armed the mechanism. The device is ready for detonation. The key on this level cannot be removed; it is now locked in place. Your key, on the other hand, can be inserted and removed again. There is a three-minute delay between the time detonation locks in and the time the bomb goes off. That period is to provide you time to think, and perhaps call it all off."
Hall was still frowning. " But why me? "
" Because you are single. We have to have one unmarried man. "