The City on the Edge of Forever is one of the best episodes of Star Trek: The Original Series, and the writer had an idea to bring it to Star Trek: The Next Generation.
Harlan Ellison wrote the much lauded “The City on the Edge of Forever” for Star Trek: The Original Series, and the episode is often named as one of the best, if not the best episode, of the series. In some instances, it’s on the best of Star Trek overall lists. So it’s no surprise that Jeri Taylor suggested Ellison write for Star Trek: The Next Generation, and he was even handed a premise that related back to the standout episode.
According to Ellison’s recollections as written in The Fifty-Year Mission—The Next 25 Years by Mark A. Altman and Edward Gross, the idea was the crew of the Enterprise would have to return to the 1930s because the aftereffects of the changes made during The Original Series had been disastrous. Somehow, Edith Keeler was still alive (as it looked like she’d been killed, but she actually wasn’t), and everyone who’d been in the show was still alive as well. Although they didn’t have the original characters, preexisting footage could have been used (much like Star Trek: Deep Space Nine did later for Trials and Tribble-ations).
The idea for a return to The City on the Edge of Forever for Star Trek: The Next Generation was rejected.
Showrunner Michael Piller quashed the idea of retracing the steps of the original Enterprise crew as not only did he think it was a mistake to tamper with an episode that so many fans held dear, he also thought it could be interpreted as a slap in the face to Gene Roddenberry.
It’s easy to want to return to what worked, but Piller was absolutely right about rejecting this idea. While Deep Space Nine successfully returned to The Original Series’ successful “The Trouble with Tribbles” later, that was a comedic episode. The City on the Edge of Forever was an emotional drama that involved the loss of love and heartbreak. Going back to undo everything that had been done in that original episode could have been a disaster. And most fans wouldn’t have looked too kindly on Edith Keeler being brought back to life after seeing Captain Kirk’s brokeness at the end of the episode.
Sometimes, it’s better to leave good things alone. It’s much better to do a creative storyline that slightly resembles the original like Star Trek: Strange New Worlds just did in Tomorrow and Tomorrow and Tomorrow.