First half of movie:
Christopher Walken and friends develop a device to record and play back stimuli to / from the human brain. Note that this was released over ten years before
Strange Days and one year before
William Gibson's first book.
Second half of movie:
Cow-orker dies while connected to brain-VCR
thingy.
The Man takes the tape for military research.
Christopher Walken decides that his life's goal is now to watch that tape.
All in all a movie well ahead of its time. Often underrated (though most DVD stores seem to burn through a lot of stock).