Adira observes the crew as they mourn Georgiou. Stamets assures them that they are a part of the crew now too. Gray appears and tries to explain himself to them.
Suddenly Stamets is alerted by the computer that there is a life form detected aboard the Khi'eth in the Verubin Nebula. Saru reveals that Dr. Isa was pregnant, as indicated by the markings visible on her forehead, at the time of her transmission. The child is likely the sole survivor of the Khi'eth's crew.
Discovery enters the nebula but is barraged by an ion storm and the radiation. Saru hesitates to leave but Book offers to take his ship in instead to scout a path for Discovery. His ship is immediately affected by the radiation and he realizes that he's being poisoned. He manages to get a scan of the life sign and transmits coordinates before the ship's autopilot kicks in to return it to Discovery.
The data shows the Khi'eth crashed into a planet made up of dilithium.
Saru informs Vance that he will accompany the away team, leaving Tilly in charge. Vance informs him that part of the fleet has been sent to Kaminar because of Emerald Chain activity. Saru offers to jump there but Burnham reminds him that Osyraa attacked Kwejian to draw Book out.
Burnham is holding Grudge in sick bay when Book recovers from the radiation. He asks Dr. Pollard to check Grudge's front left paw while she's there.
Burnham questions whether Saru is able to be objective on this mission.
Stamets tries to talk Culber out of going on the mission but Culber insists that he needs to go.
Burnham and Tilly talk before the mission. Burnham gives Tilly some advice about command.
Culber advises that they must be back in four hours or the radiation will kill them. The team beams away and Tilly takes the con.
Upon arrival, Burnham now appears Trill, Culber Bajoran, and Saru human. Their environment appears to be a forest. They realize that their supplies are missing as well.
They hear a voice and find a holo-instructor teaching about a replicator repair.
They enter a structure which appears to be crumbling. They see a chained door and several small sculptures that seem protective.
They find a Kelpian. Saru tries to explain who they are but the chained door starts to shake and the Kelpian runs away, afraid.
Burnham cautions Saru to be careful as the Kelpian is probably child-like in emotions.
On Discovery, Stamets is urging speed in repairing the shields and a garbled transmission is heard. They realize that they've lost communication with the away team.
Owo reports a Federation ship approaching. Tilly is suspicious.
Culber and Saru are greeted by another group of holos.
Burnham encounters the Kelpian's monster and tries to communicate with it. It chases her off a ledge but she falls up instead of down.
Tilly realizes the ship approaching is not Federation but is actually Osyraa. She arrives with weapons armed and Tilly orders Discovery to cloak.
Burnham wakes up on the floor near the Kelpian and pretends to be a program to keep him calm.
Culber and Saru find a holo of a Kelpian elder. They find a placard that tells Saru that the Kelpian child's name is Su'Kal.
The holo tells them that the program was created by Dr. Isa to raise and protect Su'Kal.
Burnham asks Su'Kal about his family and the memories begin to upset him. He orders the computer to reset Burnham's program parameters.
She tries to ask how to reset all parameters and that upsets him again. Burnham notices radiation lesions on her skin.
Culber urges Saru to continue with the mission. Saru examines the book the elder holds while the elder sings a lullaby which recalls to Saru memories of his youth on Kaminar.
In the book, he finds images of the sculptures which are totems of protection against the kelp monster.
Culber and Saru approach Su'Kal's fortress.
Osyraa hails Discovery. She demands the ship, spore drive, and crew. Tilly says no.
Su'Kal builds another totem in his fortress but the monster knocks it down and Su'Kal's distress emanates out, affecting Discovery and causing it to uncloak.
Tilly orders Stamets to the spore cube, planning to jump away from Osyraa. Book promises to retrieve the away team safely in his ship.
Adira has a plan and asks Reno for her com badge in order to carry it out.
Saru sings the lullaby to Su'Kal and it calms him but he still walks away.
Osyraa deduces that there's an away team with Saru on it in the nebula. As Tilly orders black alert, Osyraa's team beams aboard and take Stamets, preventing him from jumping the drive.
Book enters the nebula and contacts the team. They realize that Su'Kal caused The Burn. Book informs them that Osyraa is here. Burnham convinces Saru that he needs to stay. Culber plans to stay as well. Burnham leaves them, promising that they'll be back.
Adira surprises Book on his ship and informs him that she's beaming down with radiation meds for the team.
Burnham beams aboard, very ill from the radiation.
Osyraa's team fit a mind control device on Stamets and use it to make him navigate wherever they need.
The bridge is taken over, Osyraa takes the captain's seat.
As Burnham and Book approach Discovery, it jumps away.