“Lethe” is episode six of season one of Star Trek: Discovery.
The episode opens on Vulcan and Sarek is waiting when he is approached by another, V’Latak. A ship is brought up and Sarek says they need to leave at once as they board it. V’Latak would like to inquire as to the nature of their diplomatic mission. Sarek would like to be diplomatic by asking him to not. In times of crisis, ignorance can be beneficial.
Tilly and Burnham are running through Discovery; Burnham wants Tilly to shave off a few seconds, if she wants to make captain. Tilly thinks that what she lacks in diplomatic ability she more than makes up for in intelligence and personality. Burnham should focus on those. Burnham tells her that everyone will be smart and personality doesn’t count. Tilly responds that the latter is only said by people who lack personality. Not that she is saying Burnham lacks one. Burnham then gives her a path to captain, and Tilly starts running faster.
Lorca and the other prisoner of the Klingons that he escaped with in the previous episode, “Choose Your Pain”, Lt. Tyler, are shooting Klingons, and chatting as they do so. This is a holographic simulation, oddly; holodecks were introduced in TNG. Tyler outshot Lorca, which he tried to hide, but Lorca wants his chief of security to shoot better than he does. (the previous one was killed by the Tardigrade in “The Butcher’s Knife Cares Not for the Lamb’s Cry”). Yes, Lorca is offering Tyler a slot; he wants someone he can trust, someone who understands war, how to survive, how to win.
On Sarek’s ship he is commenting that they should soon arrive yet they haven’t dropped out of warp. V’Latak is injecting himself with something that looks to be going to make him explode. V’Latak knows the nature of Sarek’s mission, which he feels does not reflect Vulcan ideology; it seems he is what Sarek calls a fanatic. V’Latak says that Sarek’s fascination with humans can no longer be tolerated. He has been blinded to the truth, that humans are inferior. V’Latak’s sacrifice will be a rallying cry to those who value logic above all and Vulcan will withdraw from the failed experiment known as the Federation. Sarek does something just prior to V’Latak exploding, and the explosion knocks the ship out of warp.
Burnham and Tilly are now in the mess hall and Burnham is coaching her of eating, too. Tilly has seen Tyler, who it seems she thinks is hot, and heads to him. Tyler tells her she can’t believe everything she hears. Burnham introduces herself; he probably can believe everything she tells him. Before they get much further, Burnham has a vision of Sarek lying on the floor.
She is then drawn into a mind meld, something from Burnham’s past, where Sarek is with her and his wife. Burnham had been rejected from the Vulcan service, as her abilities were insufficient. Sarek will try to find her a place with Starfleet. Sarek then senses Burnham and attacks hr for being in his mind.
Jolting awake in sickbay, Burnham tells Tilly, Dr Culber and Captain Lorca that Sarek is in trouble. She explains about how they became linked after Vulcan logic extremists bombed the learning centre in order to kill her. Which they did, for 3 minutes. Sarek’s katra brought her back. She says Sarek is dying.
Terral, another Vulcan but one with Starfleet, confirms that Sarek’s ship was bombed to Lorca. Sarek was heading to a meeting of two independent Klingon houses, both of which were kicked off Kol’s ruling council. The meeting was on neutral ground in the hopes of forging an alliance to end the war. Starfleet Command is assessing what to do. Lorca decides to head off anyway.
They are unable to detect Sarek’s ship in the nebula in which he was lost, due to radioactive interference. Other ways of searching will take months. Burnham has an idea, one which Stamets thinks is his kind of crazy. Creating a synthetic mind meld augment, so Burnham can contact Sarek, wake him up and get him to activate his transponder. They won’t be able to do this outside the nebula though. Taking Discovery in would be bad. As in ‘Boom!’ A shuttle could do that, but it’s dangerous. Burnham wants Tilly’s help; Lorca sends Tyler as their pilot.
Admiral Cornwall arrives whilst they are in the nebula. She’s concerned about Lorca. The two are friends; quite close ones at that. Lorca is definitely hiding things, though, and this may well cause problems in the future. Burnham is upset that Sarek, as he is dying, is thinking of the time when she disappointed him. Tyler, who has been close to dying in the past, gives her some advice on this.