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Strange New Worlds 101: Katras

What goes on inside a Vulcan's mind?

Two illustrated Vulcans face each other on a background of purple, yellow, and orange. Yellow blobs on the Vulcans represent their katras.

Welcome back to Strange New Worlds 101! This week, we’re doing a deep dive into a key part of Vulcan culture. No, it isn’t the ritual depicted in “Spock Amok’s” opening scene as well as in “Amok Time,” but rather what causes Spock and T’Pring to engage in an accidental body swap. Let’s talk all about the Vulcan katra.

A katra is, in simplest terms, a Vulcan version of a soul. It is the essence of a Vulcan mind, that can be transferred to another person or Vulcan to preserve the mind following a Vulcan’s death. There is division amongst Vulcans over whether or not a katra is eternal and impossible to destroy; Star Trek: Voyager’s Tuvok explores his own faith with regards to this topic in the episode “Innocence.” Prior to the Star Trek: Enterprise episodes “The Forge,” “Awakening,” and “Kir’Shara,” Vulcans in the 22nd Century debated whether katras even existed. When the katra of Vulcan ancestor Surak was revealed in these episodes, this discovery helped T’Pau lead a reorganization of Vulcan society and government.

Katras were first introduced to audiences in the film Star Trek III: The Search for Spock, though they are referenced in the previous film, Star Trek II: The Wrath of Khan. As Spock faces his certain death, he touches McCoy’s face and utters the phrase “Remember.” This beat was originally placed in the film to leave the door open for a possible resurrection, and indeed it does.

Star Trek III: The Search for Spock

Spock had placed his katra in McCoy, which led to the Enterprise’s doctor seeing a blend of his personality with Spock’s (with much confusion on Kirk’s part and much humor on the audience’s). Once Sarek visited Kirk and explained what had happened, Kirk rallied the crew to find Spock’s body where it had been revived on the Genesis planet. After rescuing their friend from a group of Klingons, the crew then traveled to Vulcan so that an elder named T’Lar could perform the fal-tor-pan and restore Spock’s katra to his body.

Another key moment featuring katras was in Star Trek: Discovery. When Sarek discovered a dying Michael Burnham following an attack on the Vulcan Learning Center when Burnham was a young girl, he used his katra to bring her back. As a result, there was a lingering psychic connection between Burnham and Sarek, which Burnham used to her advantage during the Battle of the Binary Stars. Later on in the first season, during the episode “Lethe,” Burnham used her connection to Sarek to find him when he was attacked by Vulcan extremists. Their connection allowed Burnham to successfully rescue Sarek before he succumbed to his injuries.

Interestingly enough, the first recorded moment in which a Vulcan character’s “essence” is transferred is referenced was the TOS episode “Return to Tomorrow,” in which Nurse Chapel says she has been carrying Spock’s essence following a series of events involving consciousness swapping.

Spock and T'Pring (Strange New Worlds) sit on a bed while looking at each other.

In “Spock Amok,” Spock and T’Pring attempt a Vulcan ritual to better understand each other’s true thoughts. However, the result is that their katras transfer into each other’s bodies, leading to body swap hijinks. Dr. M’Benga notes that katra transfers are something he never experienced while working on Vulcan, implying they are still fairly rare at the time of Strange New Worlds. However, even without Vulcan mysticism, he and Chapel are able to transfer Spock’s katra back into Spock and T’Pring’s katra back into T’Pring, meaning all is right in the world by the episode’s end.

Relive your favorite shenanigans from “Spock Amok” in our recap, and let us know what your thoughts and theories are on social!