hermiene.net

Miniaturization is reality, but indefinite miniaturization isn't; that knowledge resides within the brain of Jan Benes, a scientist who defects to the West. Unfortunately, there is an assassination attempt which leaves Benes comatose, and a blood clot develops in his brain. A team of scientists are miniaturized and injected into Benes' body in a submarine rudimentarily outfitted with a laser and have only 60 minutes to remove the clot before they are de-miniaturized (which would make the submarine expand and in the process kill Benes).