10 Star Trek: The Next Generation Episodes That Were Almost Completely Different

It's hard to imagine that an hour of television as perfectly produced as Yesterday's Enterprise could have ever been radically different but, well, we're 7 entries into this now, you get the premise.

Interestingly though, despite feeling a million miles away from the version we eventually got, the initial idea for this episode was always about finding a way to bring Denise Crosby back in for a guest appearance. Producer Eric Stillwell bumping into her at a convention and discovering she was enthusiastic about the idea.

Calling back to the classic Orignal Series episode The City on the Edge of Forever, a Vulcan science team would accidentally change the course of galactic history when, while using the Guardian of Forever, they caused the death of Surek; the father of all modern Vulcan philosophy. As a result, the Vulcans would never discover logic, and instead become a war-like race that swept through the galaxy as would-be conquerors of races they viewed as "less enlightened".

Spock's father Sarek, being the only person unaffected by the changes would contact the Enterprise - Starfleet themselves now in the final months of a losing war with the Vulcans - and appeal to Picard to help him restore the timeline. He, along with the restored Tasha Yar, would journey to the ancient past and effectively act as a stand-in for Surek himself, while the Enterprise valiantly held off the Vulcan forces to buy them the time to do so.

Rewrites saw the Vulcans replaced with the Klingons, Sarek's role rewritten for Guinan, and Tasha Yar even, at one stage, taking command of the Enterprise-C as a historical stand-in for Captain Garrett. But in the end, the version they settled on was damn-near perfect.