Streaming service CBS All Access releases the sixth episode of Star Trek: Discovery. James Frain (True Blood) and Jayne Brook (Chicago Hope) guest star. 
Ambassador Sarek departs Vulcan on a top-secret mission to try to negotiate, on behalf of the Federation, with the Klingons to end the war. En route, he discovers that his pilot is a member of an isolationist faction that favors withdrawing Vulcan from the Federation altogether. The pilot has dosed his own body with an explosive that will destroy the ship; though injured, Sarek manages to surround himself with a force field to survive, sending part of his katra to…
…Burnham collapses in the mess hall aboard Discovery, having just received Sarek’s telepathic distress call. She is surprised when Captain Lorca agrees to go on a rescue mission over Starfleet’s objections. As the wreckage of Sarek’s ship – one piece of which contains him as he clings to life – is in a dangerous nebula, Burnham can only search for the wreckage in a shuttle, piloted by Ash Tyler, who has been appointed Discovery’s new chief of security. But when Burnham is close enough to make contact with Sarek, he seems to not want her there. A secret lies in their shared past, one that he is fighting against letting her find out, even if it means he dies with that secret.
written by Joe Menosky & Ted Sullivan
directed by Douglas Aarniokoski
music by Jeff Russo
Cast: Sonequa Martin-Green (Commander Michael Burnham), Doug Jones (Lt. Commander Saru), Shazad Latif (Lt. Ash Tyler), Anthony Rapp (Lt. Paul Stamets), Mary Wiseman (Cadet Sylvia Tilly), Jason Isaacs (Captain Gabriel Lorca), Jayne Brook (Admiral Cornwell), Wilson Cruz (Dr. Hugh Culber), James Frain (Sarek), Mia Kershner (Amanda), Kenneth Mitchell (Kol), Conrad Coates (Terral), Emily Coutts (Keyla Detmer), Julianne Grossman (Disocvery Computer), Luke Humphrey (V’Latak), Clare McConnell (Dennas), Sara Mitich (Airiam), Oyin Oladejo (Joann Owosekun), Damon Runyan (Ujilli), Jonathan Whittaker (Vulcan Director)
Notes: The katra was first mentioned in Star Trek III: The Search For Spock (1984), and Sarek’s experiences in this episode may explain why he is adamant, bordering on emotional, about finding Spock’s katra in the opening scenes of that film. Burnham’s rejection by the Vulcan Expeditionary Group was actually engineered by Sarek, who was forced into choosing between enrolling Burnham or his son Spock; he chose in favor of the latter, only to be disappointed when Spock enlisted in Starfleet against Sarek’s wishes, rending the decision pointless. (Presumably, long before this had happened, Sybok of Star Trek V fame had gone his own way.) Extremist factions on Vulcan are known to have existed a century earlier (Enterprise: Awakening), a time during which knowledge of the katra was apparently not widespread, and will continue to crop up a century later (TNG: Gambit Part II, DS9: Field Of Fire). Burnham mentions a posting to a Constitution class vessel “like the Enterprise” is a prestige assignment, even though by this point the Enterprise may well be over 20 years old (which could explain many of the differences between the looks of 
the original series and this series). As The Cage happened three years prior to Star Trek: Discovery, Burnham may have Spock in mind when she says this. The Discovery has at least a rudimentary holodeck, though it would seem that it is used only for combat simulations. (23rd century holodecks are not an anachronism, however: the animated episode The Practical Joker clearly shows a “holographic environment simulator” aboard the Enterprise.) In Greek mythology, the river Lethe would cause those who drank from it to forget, as presumably Sarek would like to.
LogBook entry by Earl Green