A famous scientist got shot by Commies just before he was about to relay an important discovery and is lying in a coma, with an inoperable blood clot in his brain. That is, inoperable by standard means. Putting a bunch of doctors in a submarine, shrinking really small and injecting them into the scientists body might work. The movie's premise is ridiculous, but it's not as bad as it sounds, which means of course it's not as good. It's like a sub-par Star Trek episode inside the human body, without any of the fun dialogue. There is cliché after cliché, but I did like the part where the crew discovers that one of them is actually a Commie double agent. But who is it? It couldn't be the most obvious person, could it? Aside from Pleasence, all of the actors, who include Rachel Welch and Stephen Boyd (Messallah from Ben-Hur) are wooden. The movie is fun in a stupid kind of way for awhile and then gets boring. The special effects are bad, but that's OK. Fantastic Voyage (1966)