As the crew of the USS Discovery gather to remember the Terran they love to hate, Stamets (Anthony Rapp) encourages his unofficially-yet-officially adopted teen Adira (Blu del Barrio) to build connections with others. They are reluctant to engage when Gray (Ian Alexander) finally returns. Protective SpaceDad is protective, but leaves the two of them to reconcile Gray’s abrupt absence.
Just as they patch things up, Stamets receives a notification that the analysis of the Kelpien ship Khi’eth has revealed a life sign on the ship. Capt. Saru (Doug Jones) is understandably taken aback. Tilly (Mary Wiseman) asserts that not only did the Khi’eth crash before the Burn, over a century ago, but the radiation from the Verubin nebula should have made survival impossible for the Kelpien doctor who sent the message. Saru then reveals that Dr. Issa was pregnant in her message.
Jumping to the Verubin nebula, the crew discovers the violent storm inside. Detmer (Emily Coutts) warns them of the incoming turbulence, but Saru urges them onward as scans are disrupted by the storm. Burnham (Sonequa Martin-Green) urges Saru to back off as DISCO takes damage from the nebula’s ionized radiation. Book (David Ajala) volunteers his smaller, more maneuverable ship to explore instead, and Saru reluctantly agrees.
Once inside, Book manages to find the planet, but not without suffering from radiation exposure. He sends the lifesign’s coordinates to DISCO as well as a safe pocket inside for them to jump to just as the radiation exposure gets extreme, and his ship’s autopilot brings him back to the shuttlebay mostly in one piece. Tilly examines the coordinates to reveal a planet ripe with dilithium deposits.
Doing their due diligence and notifying Starfleet command straight away, Admiral Vance (Oded Fehr) is understandably taken aback by the notion of a planet composed primarily of dilithium. Vance reluctantly permits DISCO permission to rescue the lifesign and recover any information they can. Vance alerts the captain that the Emerald Chain has begun military exercises near Kaminar, to which Burnham recounts how the Chain pulled a similar tactic back at Kwejian. Pushing through anyhow, Saru forms an away team of himself, Burnham, and Dr. Culber (Wilson Cruz) to investigate the planet, vouching for Tilly under the admiral’s withering scrutiny.
In sick bay, Burnham and Her Majesty, Queen Grudge await a newly recovered Book. Dr. Pollard (Raven Dauda). Book asks Dr. Pollard to take a look at Grudge’s front paw, and walks with Burnham to debrief. As he marvels about the amount of dilithium inside the nebula, Burnham updates him on her mission to the planet and the dangers that could await them.
Stamets and Dr. Culber have a similar conversation in navigation, except Book handled the news much better than Stamets. Incensed, he vigorously protests, listing all of the reasons why Culber shouldn’t go, but Culber insists. As they talk it out, Adira and Gray look on. Tilly, meanwhile, joins Burnham in their quarters for a last minute pep talk. Burnham encourages her friend as she takes the con for the first time, reminding her of her skills and achievements thus far.
DISCO jumps inside the nebula to the coordinates Book found during his scout mission. Deciding to land on the Khi’eth for its additional radiation protection, Dr. Culber explains the brief 4 hour window they have for survival. As the away team assembles, Saru hands command over to Tilly before beaming to the lifesign’s coordinates. The away team appear on the planet individually, in new clothes and surprising new features. Culber is suddenly Bajoran, Burnham is Trill, and as Saru joins them, each of them are shocked to find him human.
Determining that they landed on the ship and not the planet itself, the team surmises that they’ve landed within a computer simulation. Concerned about their lack of meds and supplies, Culber reminds them of their time frame. After trying and failing to raise DISCO on the comm, they decide to investigate a sound nearby.
Stumbling upon a stuttering holo, the away team deduce that they’ve landed within an immersive educational program, and the program assigned them new appearances to match data within its hundred-year-old memory banks. The program degrades, and the team discovers a nearby structure in ruin. They come across a huge, chained door and collections of ceremonial rock structures. Hearing a voice in the distance, they find a startled Kelpien who insists that they’re rogue programs in the wrong place. Saru tries to explain who they are, but at the mention of an outside existence, whatever those doors are holding back tries to burst through. The Kelpien hurries off, and Burnham surmises that the survivor must be handled delicately. Culber agrees, and Burnham stays behind to examine what was behind the doors so that Saru and Culber can follow.
Back on DISCO, Stamets is geared up, shouting orders to ensure the ship is ready to jump back inside the nebula within that 4 hour window. On the bridge, Tilly asses that they can’t go back until the shield integrity is higher. Owosekun (Oyin Oladejo) alerts them that long range scanners have picked up an incoming Federation vessel. The bridge crew bat around guesses as to who it could be. Dubious, Tilly has Bryce (Ronnie Rowe, Jr) hail the vessel, but receive only response codes in reply, stating that the vessel is 10 minutes out.
On the Khi’eth, Culber and Saru find a glitchy and outdated orientation program, where they determine that the survivor has been in the care of the computer since the Burn. Burnham investigates the creature within the doors, giving us a god look at the murky figure. She attempts to communicate with the being, but it lashes out and chases her around the structure. Burnham accidentally steps off a ledge and is tossed upwards through what appears to be a gravity well instead falling to her death.
Meanwhile, Tilly and the bridge crew try to solve the mystery behind the incoming vessel. Just as they figure it out, Osyraa’s ship, the Viridian, decloaks before them. Deciding not to jump away to protect the away team, Tilly orders DISCO to cloak (‘cause apparently they can do that since the retrofit!) to buy some time to weigh their options.
Back on the Khi’eth, Burnham regains consciousness and finds the survivor timidly watching her. Assuming she is a new program, the survivor (Bill Irwin) is thrilled to find a program he hasn’t interacted with yet. Burnham describes herself as a program designed to instruct social skills as interactions with sentient beings require instructions. The survivor insists that outside no longer exists and that her information is obsolete, but pleads her to teach him anyway.
Saru and Culber investigate further and come upon a storytelling program portrayed by the oldest Kelpien Saru has ever seen (Robert Verlaque). They discover the survivor’s name is Su’Kal after a Kelpien survival tradition, and bounce back and forth between several scenes of Saru learning from the elder program and Burnham attempting to gently bring Su’Kal up to speed. Learning that the entire program had been designed by Dr. Iso to raise and protect her son until a rescue was made, confirms Burnham’s theory to treat Su’Kal like a child to ensure cooperation with their mission. Culber and Saru set off to find the fortress where Su’Kal hides when he’s troubled.
On DISCO, Tilly, Book, and the bridge crew bat around theories as to just what Osyraa is up to. Engineering gives 30 minutes before shields will be strong enough to jump away just as Osyraa (Jane Kipper) hails them. Tilly answers and after some banter, she proceeds to confirm why she belongs in that chair.
Burnham finds the skittish Su’Kal inside the structure as Culber and Saru join her. Together they watch as the creature holo descends upon Su’Kal, and when he cries out in fear, a powerful shockwave fans outwardly. Resonating as far out as to reach both ships waiting outside the nebula, Stamets, Adira, and Reno (Tig Notaro) hustle to stabilize the ship’s dilithium in the wake of the disturbance. Tilly decides to jump away, and Book volunteers to stay in the nebula for the away team when Stamets protests.
On the Khi’eth, Su’Kal is still alarmed until Saru sings a Kelpien lullaby, soothing the survivor as the creature holo slips away. The disturbance subsides, and DISCO is once again hailed by Osyraa. Tilly takes the call, ordering Owosekun to notify the moment Book is clear so they can jump to safety. Quicker on the draw, Osyraa beams over troops before DISCO can jump, and the ship is captured swiftly.
Book reaches the away team informing them of the situation outside, and begs them to prevent the disturbance from happening again. They realize that Su’Kal, after years of exposure to dilithium and such high levels of subspace radiation, may have actually caused the Burn. After debating a bit, they decide that Saru and Culber will stay behind to try to encourage Su’Kal to confront both his literal and metaphorical demons while Burnham returns with Book.
As Book searches for Burnham’s signal amidst the radiation, Adira pops up on the bridge. With Reno’s badge and radiation meds, they beam down to the Khi’eth right before Burnham beams aboard. Together they rush back, Burnham promising to explain along the way.
In engineering, the Chain boarding party corrals the crew as Stamets demands their release. They crown him with a neural control device and take full control of the spore drive. Osyraa and her soldiers take the bridge, and jump back to Federation headquarters just in time for Burnham and Book to watch them get away.
Did Adira bring enough meds with them before transporting down to the most volatile spot in the galaxy? Will Saru and Culber manage to convince Su’Kal to mellow out? Can Burnham and Book make it to FHQ in enough time to help DISCO? With only two more episodes left in season 3, the stakes have officially risen and tension is set. The Discovery and her crew have been through a lot, but will it be enough to prepare them for their toughest foe yet?