WARNING: The following contains spoilers for Star Trek: Discovery Season 3, Episode 7, "Unification III," now streaming on CBS All Access.

As the investigation in Star Trek: Discovery continues into what exactly triggered The Burn, the event that combusted all known dilithium in the galaxy and caused the Federation to splinter, the Discovery finds itself face-to-face with Spock's diplomatic legacy -- picking up from a major plotline established during the iconic character's appearance in Star Trek: The Next Generation. That mission is the reunification of the Vulcan and Romulan civilizations on their mutual homeworld. While the two societies have reconciled and come back together, they have since split from the Federation in the immediate fallout from The Burn.

In a two-part story during The Next Generation, it was revealed that Spock had retired from his lengthy Starfleet career to become an ambassador for the Federation. Spock's most ambitious diplomatic mission had him travel to Romulus, the central planet of the Romulan Star Empire, to secretly bring about peace and reunification between Vulcans and Romulans. Spock had successfully initiated the peaceful reconciliation between the Federation and the Klingon Empire during Star Trek VI: The Undiscovered Country and was determined to broker peace between his people and their Romulan offshoots in his lifetime. In Episode 7 of Discovery, Michael Burnham reviews archival footage of her adopted brother explaining the importance of his mission.

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Spock met underground Romulans intent on brokering a peace before Jean-Luc Picard and his crew discovered it was all part of an elaborate plot by the Romulans to conquer Vulcan. A latter bid by the Romulans was made for peace after teaming up with Starfleet in Star Trek: Nemesis to battle the villainous Shinzon who had staged a violent coup and attempted to attack Earth in a new advanced starship. Peace would eventually be realized after a supernova consumed Romulus, prompting an influx of Romulan refugees to the Federation that would be explored in the first season of Star Trek: Picard.

Discovery reveals that in the centuries since Picard, the Vulcans and Romulans shared their planet and renamed it Ni'Var to reflect their shared origins and heritage. While the merged civilization reflects more of the classic, logic-driven ideologies that were the bedrock for Vulcan culture, some of the more aggressive and manipulative tendencies of Romulan society resurface as a senior council from Ni'Var hear Burnham's testimony for the civilization to share their information on the experimental transportation system SB-19 with the Federation to continue the investigation behind the Burn.

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Spock's legacy is still revered by the Vulcans and Romulans of Ni'Var, accepting the Federation envoy only after learning Burnham was among the ship's crew. Initially obstinately resistant against the possibility of any normalization of relations with the Federation, Burnham reminds Ni'Var of Spock's vision of a galaxy working together towards building a unified utopia. Ni'Var may not be back in the Federation yet but the legacy of Spock's push for wider unification suggests that the lessons from The Next Generation may help the Federation rebuild centuries later, with Spock's mission already proving that peaceful coexistence remains a distinct possibility.

Star Trek: Discovery Season 3 stars Sonequa Martin-Green as Commander Michael Burnham, Doug Jones as Captain Saru, Anthony Rapp as Lt. Commander Paul Stamets, Mary Wiseman as Ensign Sylvia Tilly, Wilson Cruz as Dr. Hugh Culber, Blu del Barrio as Adira, David Ajala as Cleveland “Book” Booker and Michelle Yeoh as Philippa Georgiou. A new episode arrives on CBS All Access every Thursday through Jan. 7, 2021.

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