Nimoy noted that he and producer Harve Bennett initially thought up a time-travel story for “Star Trek IV” and that “we should lighten up. The picture should be fun in comparison to the previous three.” Nimoy also wanted the film to be centered on ecology and visited several universities to talk to environmental scientists and futurists to get their immediate concerns about the future. Ultimately, Nimoy said, those conversations spun off into philosophy and theory, leading to some deep consideration about how human contact with extraterrestrials might potentially change notions of religion and sociology. Fun conversations, to be sure, but not quite what Nimoy needed to form a story for a “Star Trek” script.
It wasn’t until he met with a particular author that notions of biodiversity — as a direct story element — began to enter Nimoy’s mind in earnest. The director said:
“In [Edward O. Wilson’s] book Biophilia, he tells us we could be losing as many as ten thousand species off this planet per year—many of them having gone unrecorded. We won’t even have known what they were and they will be gone. He touches on the concept of a keystone species. If you set up a house of cards you may be able to pull away one card successfully and another card successfully. But at some point you are going to get a card that is a keystone card. When that one is pulled away, the whole thing will collapse.”
Wilson’s book is easy enough to find online.
The “keystone,” Nimoy pointed out, could be any species on Earth, and that it was wise to protect them. Throughout the 1980s, the slogan “Save the Whales” was largely touted on bumper stickers and by environmental activists.
Lo, there was Nimoy’s “hook.”