Air Force trainee (Matthew Broderick) is caught with a girl in a plane and is punished by being sent to a research facility where they train chimpanzees to fly with flight simulators. He becomes attached to one chimp in particular named Virgil, who was trained to speak sign language by Helen Hunt. Eventually he learns that the chimps are subjected to deadly experiments. So he seeks out Virgil's trainer so they can try to save the chimps.
Obviously this is an easy movie to deride. With its animal rights and anti-military themes, it's going to lose some audience members at the door. I'm not saying that the movie is completely fair on these issues. It's a pretty clear black & white/good vs bad kind of story that tugs at the heartstrings more than it engages the mind. But it does it very well. I enjoyed the movie a lot despite not agreeing with its oversimplified viewpoints 100%. Broderick and Hunt were great but the chimps really steal the show. It's hard not to feel sympathetic towards their plight. I also liked the ending, which many seem to think is silly. It was Disneyesque but appropriately hopeful. It's a good film. Check it out if you're not overly cynical.