Star Trek IV: The Voyage Home (1986)
Saucer-People 1 points 2 years ago. (Contains Spoilers)

Don’t think I ever watched it again after seeing it at the cinema when it came out but I’m so glad I took the opportunity once more as it is one of those ‘enjoyable sci-fi romps’ with a great ecological message and quality acting from the original team.
Interestingly, in the same year this was released, commercial whaling was finally banned and ever since the humpback whale population has increased to nearly 100’000 from its imminent threat of extinction only a few decades ago.