Sarek and a younger Vulcan depart on a diplomatic mission that Sarek does not share the details of.
Burnham and Tilly are running together and Burnham is drilling Tilly on how to achieve her dream of becoming a captain. It inspires Tilly to run faster.
Lorca and Tyler take on some Klingons in a simulation. Lorca questions Tyler and reveals that he's had him checked out. Tyler lies about how many kills he took down in the simulation. Lorca offers him the position of Chief of Security and he accepts.
Sarek realizes that his companion has sabotaged the flight plan and knows the nature of his mission. The other Vulcan states that humans are inferior and the Federation experiment shall fail with his suicide mission. Sarek manages to escape the explosion.
Burnham and Tilly sit down to eat with Tyler. When Burnham shakes his hand, she suddenly connects psychically to Sarek who is badly injured. She is transported to a memory of the day Sarek proposed finding a place in Starfleet for her. She sees Amanda pleading that he help Burnham get a position with the Vulcan Expeditionary Group. Sarek sees the psychic image of the present-day Burnham and ejects her from the memory.
Burnham awakes in sick bay. She explains her connection to Sarek and that he shared his katra with her when Vulcan extremists murdered her in order to save her life. She believes that he is near death.
Starfleet Command reveals that Sarek's vessel was sabotaged and that he was on his way to negotiate a treaty with two of the Klingon houses.
A very cheerful Stamets agrees to use Burnham's connection to boost and wake Sarek. He warns that she'll need to get into the nebula in order for this to work but the Discovery can't go in. She decides to go in in a shuttle with Tilly and Lorca assigns Tyler as pilot, telling him that he'd better bring Burnham back safe or don't come back at all.
Admiral Cornwell docks on the Discovery and meets with Lorca to condemn his plan to rescue Sarek. She questions his methods and the crew he chooses to employ. When they establish that they're still friends, Lorca pulls out a bottle of liquor.
In the shuttle, Burnham has Tilly activate the mechanical mind meld machine and tells her to not bring her out no matter what the machine says. In the memory, Sarek tries to eject her again. They fight and the monitors indicate Burnham is in danger and Tyler orders Tilly to pull her out.
In his quarters, Cornwell and Lorca share a drink and discuss Lorca's ability and decision-making. They reminisce over a romantic past and Cornwell removes her communicator.
On the shuttle, Burnham insists they let her go back in and Tyler and Tilly try to help her with how to get through to Sarek.
Back in the memory, Burnham confronts Sarek and he allows her to see the conversation he had with the Vulcan Expeditionary Group where he actually chose to support Spock's application and allow the group to reject Burnham. Having made his confession, he shows Burnham how to save him.
She successfully revives him and he activates the ship's distress signal. The shuttle is able to find him.
In bed, Cornwell examines a scar on Lorca's back and he reacts by pulling a phaser on her. She accuses him of lying on his psych evals and fooling everyone. She threatens to take the Discovery away from his command and he begs her not to.
Sarek recovers in sick bay but cannot continue his mission. Lorca suggests Cornwell be sent instead. He offers Burnham the position of Science Specialist on the bridge and she accepts.
Burnham visits Sarek in sick bay but he refuses to acknoledge the memory and mind meld they shared and won't discuss it with Burnham. Burnham lets it go, telling him that they will have the conversation one day.
Lorca sees Cornwell off in a shuttle. She tells him that when she gets back, she will have his command revoked, have him submitted for treatment and hopefully get him back in the captain's chair.
In the commissary, Tyler offers Burnham a seat and they discuss Sarek and Burnham's feelings after the rescue. Tyler diagnoses them as purely human.
On Cancri IV, in the Neutral Territory, Cornwell arrives for the talks and it turns out to be a trap. Her escort and the hosts are killed and a holographic communication with Kol confirms that one of the Klingons present is Dennas and that the two houses have proven themselves worthy of cloaking technology by securing a Starfleet hostage.
When Lorca is informed that the Admiral has been taken, he instructs Saru to contact Starfleet command for orders rather than pursue the Admiral's abductors.