Summary
Robin Curtis says that her version of Lieutenant Saavik inStar Trek III: The Search for Spockwas less emotional than Kirstie Alley’s because of director Leonard Nimoy.Kirstie Alley originated the role of Lt. Saavik inStar Trek II: The Wrath of Khan, which was directed by Nicholas Meyer. Saavik was a protégé of Captain Spock’s (Leonard Nimoy), and she served on the USS Enterprise under Admiral James T. Kirk (William Shatner) during the conflict that resulted when Khan stole the planet-creating Genesis Device,
WhenStar Trek III: The Search for Spock’s production wouldn’t meet Kirstie Alley’s fee to return, Robin Curtis was cast as Lt. Saavik. Along with David Marcus (Merritt Butrick), the son of Admiral Kirk, Saavik surveyed the newly created Genesis Planet, where she found Spock resurrected.Saavik helped Spock through pon farr, and kept him safe as Spock underwent a painful aging process. But after Spock was returned to Vulcan and reunited with his katra, or Vulcan soul,Lt. Saavik remained on Vulcanat the beginning ofStar Trek IV: The Voyage Home.

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Leonard Nimoy Is Why Robin Curtis' Saavik Was Less Emotional Than Kirstie Alley’s In Star Trek III
Nimoy made Saavik a more traditional Vulcan
Appearing onThe Sci-Fi Dinerpodcast, Robin Curtis addressed the question of why her version of Lt. Saavik inStar Trek III: The Search for Spockwas less emotional than Kirstie Alley’s Saavik inStar Trek II: The Wrath of Khan. Curtis' more cerebral Saavik was a noticeable departure, especially after Alley’s Saavilk cried at thedeath of Spock inStar Trek II.Robin explained thatStar Trek IIIdirector Leonard Nimoy made Saavik more Vulcan. Read her quote and watchThe Sci-Di Dinervideo below:
I admit it was very much direction. But it was my preference to be that actor who just put herself in the hands of the King Vulcan. Who was I to go into the franchise and go, ‘Well, you know, this is what I think a Vulcan woman would do and say.’ I shook Mr. Nimoy’s hand the first day of work, and said, ‘You seem to think I know what I’m doing, but I really don’t.’ And he said, ‘Robin, I’ll take you every step of the way.’

And so, when people comment on the subtle differences or perhaps some of the more obvious differences between the two portrayals, I have to remind them I think it’s very much a collaboration between the artist and the director, for sure. Obviously, Nicholas Meyer and Kirstie kind of went to the edges of the emotion and the flirtation, and they brought some nuances to the character that Leonard Nimoy would have no part of. He didn’t want me to breathe in the wrong place, as much as I tried to inject that little layer of emotion. It wasn’t happening. He wasn’t having it.
While it was not outright stated inStar Trek II: The Wrath of Khan,Lt. Saavik was meant to be half-Vulcan and half-Romulan. This explains whyKirstie Alley’s portrayal of Saavikdisplayed myriad emotions, from an attraction to Admiral Kirk to outright grief at the death of Spock. However,Leonard Nimoy had very specific ideas about Vulcanssince he originated the logical species' portrayal, and Ninoy worked closely with Robin Curtis to make Lt. Saavilk more Vulcan than Star Trek IIdirector Nicholas Meyer preferred Alley to play Saavik.

What Happened To Saavik After Star Trek: The Original Series' Movies
Star Trek: Picard season 3 updated Saavik’s Starfleet career
Lt. Saavik hasn’t appeared in aStar Trekmovie or TV series sinceStar Trek IV: The Voyage Home, althoughRobin Curtis appeared inStar Trek: The Next Generation’s “Gambit” as the Romulan Tallera. However,Star Trek: Picardseason 3 delivered a long-awaitedupdate on what happened to Saavik. According to ancillary background forStar Trek: Picardseason 3 that was posted on Instagram, Saavik was promoted to Captain of the USS Titan in 2293, after the events ofStar Trek VI: The Undiscovered Country. Captain Saavik’s Titan was even briefly the flagship of the United Federation of Planets.
Saavik was originally meant to become a traitor inStar Trek VI: The Undiscovered Countrybefore Kim Cattrall’s Lt. Valeris was created.
Star Trek: Picardseason 3 briefly acknowledged this bit of background info by showinga piece of a shuttle from the USS Titan-A that bore Saavik’s name. TheTitan’s shuttle was a nod to Captain Saavik’s command of the previous 23rd century incarnation of the starship. While Kirstie Alley’s Lt. Saavik is still considered the defining version of the role; Robin Curtis' Saavik is, indeed, more Vulcan thanks to Leonard Nimoy, and Lt. Saavik was an integral part ofStar Trek III: The Search for Spock.