Warning: SPOILERS for Star Trek: Discovery season 3, episode 7, “Unification III”.

Star Trek: Discovery season 3, episode 7 features a surprising but welcome cameo from arguably the franchise’s most iconic character – Spock, once again portrayed by the late Leonard Nimoy. Having traveled almost a thousand years into their relative future, the crew of the Discovery have finally reunited with what remains of Starfleet. The ship has been retrofitted both to fit in with the technology of their new era as well as to obfuscate the fact the ship is from the past, as time travel was outlawed after the Temporal Wars.

In an effort to learn more about the Burn, the Discovery is tasked with securing information about an experimental propulsion project called SB19 from the planet Na’Vir, which was formerly known as Vulcan. To Michael Burnham’s shock, the Vulcans and Romulans reunified in the intervening centuries (seeing as how no human saw a Romulan before the Star Trek: The Original Series episode “Balance of Terror”, Burnham would have been unaware that Romulans and Vulcans were the same race).

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While reading up on her new mission, Burnham learns that her little brother, Spock, was the catalyst for reunification. In an incredibly emotional scene, Burnham accesses a video file from the archives of Admiral Jean-Luc Picard, which turns out to be a scene from the Star Trek: The Next Generation episode “Unification, Part 2,” in which Leonard Nimoy reprised his role as Spock. Spock articulates his reasons for leaving Starfleet behind to embrace the dream of reunification in the powerful, logical way that only he can.

This is actually not the first time Star Trek: Discovery has showcased the late, great Nimoy. A season 2 episode featured a recap of the original TOS pilot “The Cage” that briefly glimpsed the original version of Spock, rather bizarrely smiling at a singing flower (in reality, this was before the repression of all emotion was part of Vulcan lore). But this appearance by Nimoy is far more powerful, as it reaffirms Burnham’s belief that Spock was destined for greatness. It’s also, quite frankly, one of Nimoy’s finer moments in the role of Spock, explaining to Picard the mission that he’s taken on and why the Romulan people are worthy of his efforts. It’s a quintessential moment in Star Trek history, and its reframing here is no less powerful.

Star Trek: Discovery has taken a bold leap forward in season 3; the future setting means it’s no longer hampered by prequel considerations, yet there’s a sweet irony in the fact that it’s most touching moment is in fact a callback to those prequel roots. This is likely the last time audiences will see Nimoy as Spock within the overall fiction of Star Trek; if so, it’s a more than worthy sendoff.

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