USS Discovery floats in space as DOT-7 drones repair the ship. Doctor Hugh Culber conducts examinations of the crew, who are still processing the leap forward in time. He finds them physically well but psychologically stressed. In a voiceover log entry, he notes that the ship’s goal of searching out the remaining Federation members has provided motivation for some crew members while leaving others detached. He offers to talk to Keyla Detmer, who is taking it harder than many on the ship, but she declines.
Adira undergoes medical scans in attempts to retrieve her memories from the Tal symbiont. Culber and Dr. Tracy Pollard find that the symbiont is wrapped around Adira’s heart, which she says is to protect her. She remembers nothing of her life before the joining; noting that she can remember how to speak seven languages and make Bajoran hasperat but her earliest memory is being in an escape pod before being rescued by the United Earth Defense Force. Culber suggests that they travel to Trill to seek the help of experts on the symbiont, and Adira agrees.
Using the spore drive, Discovery jumps to Trill and goes to yellow alert, wary after their reception at Earth. They open a channel to the planet and receive a holographic reply from Commissioner Vos, who says the Trill population was decimated by The Burn and is excited to encounter a returning symbiont. Captain Saru says he will send the host and a medical officer to the planet, though he does not mention Adira is Human, not Trill.
In engineering, Saru approaches Paul Stamets to discuss his health – and more broadly, the risk posed by having a single person capable of operating the spore drive, especially with the era’s dilithium scarcity.
Stamets is defensive, noting he researched the matter for more than a decade before the discovery of the tardigrade aboard the USS Glenn allowed him to make controlled jumps. Saru notes there has been over nine hundred years of technological developments since then and that alternatives are necessary in the event Stamets should ever again be incapacitated.
Culber visits Burnham in her quarters as she reviews clues about The Burn that she collected during her year alone. Culber asks Burnham to accompany Adira to the planet to provide emotional support since she has experienced a similar feeling of disorientation and loss. Culber describes post-traumatic growth, a means by which people can grow and evolve after a difficult life event like nearly dying or being isolated. Burnham worries she wouldn’t be able to function in this role, but he calls her a “responsibility hoarder” who focuses on work during times of emotional struggle.
As they approach the shuttlebay, Adira questions why Burnham is accompanying her to Trill and decides to go alone. However, after a few seconds she changes her mind, saying she does not wish to let anyone down. Boarding Shuttlecraft 31, Adira also jocularly urges Burnham not to say anything “annoyingly inspirational,” to which Burnham laughs and agrees.
In the captain’s ready room, Culber delivers his report to Saru; the crew is “physically sound,” but not “healthy.” They are experiencing high anxiety due to their solitary circumstances. Saru wants to help, but the typical Starfleet remedies of duty and routine may not be effective, Culber says. Because Discovery is unknown in 3189, the crew needs to feel connected.
On Trill, Burnham and Adira land and walk through a lush forest where flying fish leap from ponds. They encounter Vos, along with Guardian Xi and Leader Pav, among others. Burnham introduces herself and Adira. The Trill are confounded to see a non-Trill host. Xi asks Adira to speak her names, but she can only respond with “Adira.” Vos notes there is no record in over two thousand years of a successful joining between a symbiont and a non-Trill species and calls Adira’s joining with Tal an abomination.
Vos suggests excising the symbiont, though Xi warns forced separation would kill the host, alarming Burnham. Xi apologizes and explains that Trill society and the population of Trill who could be joined was devastated by The Burn and its aftermath, with the survival of their culture through joining in doubt. He says symbionts joining with Humans could be a solution to their problem. Pav decides that they will not forcibly remove the symbiont, but agrees with Vos that the joining is an aberration. She orders Adira and Burnham to leave the planet immediately.
As Burnham and Adira walk away from the meeting towards their shuttle, they are accosted by Vos and two men with bladed weapons. They prepare to kill Adira to recover the symbiont, but Burnham pulls out a phaser and stuns the two guards. Vos refuses to tell her where to find the Caves of Mak’ala, and Burnham stuns him as well, which Adira notes is not Federation protocol. Xi approaches and offers to show them the caves.
On Discovery, Saru consults the computer as to how to “heal [his] crew.” The computer’s voice changes and it chuckles. It recommends silent film comedies by Charlie Chaplin and Buster Keaton. Saru, perplexed, orders it to perform a level 10 diagnostic, but the computer replies that it is fully operational. The computer also suggests giving the crew a night off or inviting them to a meal.
On Trill, Xi leads Burnham and Adira to the sacred pools in the Caves of Mak’ala. He notes that as the symbionts’ ancestral home, it is the most likely place for it to communicate with Adira, who says the caves feel safe. Adira asks Burnham to say something inspirational before she enters the pools. Michael tells her to get in “before someone shoots us.”
Saru hosts a dinner party in his ready room. He announces he has given the rest of the crew the evening off and that the dinner for the bridge crew is to be a ritual to “take the measure of loved ones and what we’ve all accomplished together.” He reminds the crew of the “small prayer” they said before they leapt into the future, “Aye,” though Philippa Georgiou playfully notes she did not cast such a vote. They toast one another, again saying “Aye.”
In the cave, Burnham asks if Adira may have been joined against her will. Xi says symbionts cannot survive in an unwilling host, and that Adira must face whatever the issue is. Adira, dressed in a traditional white gown, walks into the pool. For a few moments, Adira floats on her back, and as sparks dance across the water’s surface, her eyes flash fully white; Adira is now “in communion” with the symbiont.
At Saru’s dinner party, the crew eats quietly. Culber inquires about tension between Stamets and Tilly, but Stamets deflects the inquiry. Saru tells a story of his life on Kaminar, and the crew pivots to playing a game where they try to speak in haiku. Detmer refuses to participate at first, before starting to form a haiku about Stamets’ blood. She refuses to stop as Stamets protests and the rest watch awkwardly. He cites his rapid return to duty after being injured, but Detmer argues that all of their jobs are important. Tilly enters the fray and tells them to be united as a crew. Stamets and Culber walk out, followed by Detmer, then the rest.
Meanwhile, on Trill, Adira is in distress. Burnham attempts to enter the pool, but Pav, Vos, and several guard enter and stop her. Adira begins to hyperventilate and twitch in the pool before disappearing beneath the milky liquid. Pav reluctantly agrees to let Burnham enter. The Trill deploy neural stabilizers to allow her to commune with Adira for a short time.
Burnham finds herself in a strange place with colorful threads floating through the air. She finds Adira, who says she is trapped and confused. One of the threads touches Adira’s foot and she reacts with pain; if she remains in one place for more than a few seconds, the threads attack her. Burnham surmises Adira is in this place to connect with her symbiont and that the threads are attempting to connect with her, not harm her, that they are connected to the symbiont’s memories.
Adira allows multiple threads to connect with her fingertips. Suddenly, she accesses a memory of herself in a medical bay standing over her lover, Gray, a Trill about to receive the symbiont. In the memory, they hold hands as Adira wonders whether Gray will be the same after the joining. In the thread space, Adira tells Burnham that she and Gray were both orphans aboard a generation ship searching for Federation headquarters. Stressed, Adira tries to walk away, but Burnham tells her she cannot leave until she accesses the full memory.
In her memory, Adira sees Gray, now joined with the Tal symbiont, playing cello in their quarters. She tells Gray that he promised he would be the same after the joining, but that his newly-gained skills made him “kind of perfect.” Gray jokes that he “already was perfect” but insists he is still himself, just more so. However, Adira questions what is truly Gray and what comes from the prior hosts.
Adira marvels that he is able to navigate the joining so well, and he assures her the joining is based on trust between symbiont and host, just as he trusts Adira. She presents him with a handmade art gift, but as Gray opens the box, Adira pulls out of the memory, telling Burnham to back off. She accuses Burnham of being interested only in the message from Senna Tal, but Burnham says her interest is in securing a future for everyone and that Adira will never move forward without facing whatever painful memory she is suppressing.
Adira re-enters her memory as Gray opens her present. She explains that many cultures pass on stories via tapestries or quilts, with each piece representing a special moment or person. On the quilt she stitched for Gray, one panel depicts an instance in which they broke a replicator and it would not stop producing apples. Another shows a time they played imaginary chess. Gray says he loves it and calls Adira an “art genius.” Suddenly, an asteroid impacts the ship, severely damaging their quarters. Adira calls for medical drones to attend to Gray, who has been impaled. The drones determine Gray will not survive treatment, but that the Tal symbiont can be saved. Adira volunteers to become a host, knowing that the memories of Gray and all the prior hosts would be lost otherwise.
Exiting the memory into the now-calmed neural space with Burnham, Adira is greeted by manifestations of the prior Tal hosts, including Senna and Gray. Senna notes that a Human joining is unusual but says Tal accepts Adira as a host. Burnham tells Senna that his message gave her hope. The manifestations disappear, and Adira and Burnham emerge from the milky waters in the cave pool.
Xi asks Adira again to speak her names. She responds: “I am Kasha Tal. Jovar Tal. Madela Tal. Cara Tal. Senna Tal. Gray Tal. And I am Adira Tal.” The other Trill apologize for their prior treatment of her and say she will impact generations of Trill to come. Pav offers to mentor Adira, but she decides to stay with Discovery as it seeks out Federation headquarters. Pav hints that when the Federation returns, Trill would consider joining.
On Discovery, Saru mopes over the remains of his ruined dinner party as Tilly returns to thank him. Saru laments that Captain Christopher Pike made connecting with the crew seem effortless. Tilly says that the crew decided together to travel into the future and are living together with the consequences of that decision, but that Saru’s reminder of their connection shows leadership. Stamets enters and tells Tilly he has failed to appreciate her contributions and apologizes. He inquires about her spore drive research. Tilly says she was examining dark matter and energy coefficients but that she could not make the math work. Stamets says her idea would be revolutionary and that they should research it further.
In sickbay, Detmer approaches Culber and says she obviously is not okay but that it was hard to admit. She accepts Culber’s offer to talk sometime. Then the computer directs available crew to the shuttlebay for a surprise. There, the crew is watching a holographic projection of the 1924 Buster Keaton silent film Sherlock Jr.. The crew laughs, and Linus hands the aloof Georgiou a box of popcorn. Detmer and Stamets silently apologize and embrace. In the rear of the crowd, Culber notes to Saru that the crew had to admit they were not “fine” before they could begin to feel joy and heal. Saru reveals the movie was the idea of the Sphere data that has begun to integrate into the ship’s systems. The crew worked to protect the data, and it now is trying to protect the crew, he speculates.
In her quarters, Adira tells Burnham that Senna knew the necessary algorithm to find Federation headquarters, handing Burnham a PADD with the coordinates already entered. Adira pulls out a cello and plays a lullaby that she says was sung by Senna Tal’s parents when he was a child. Her past hosts’ memories are slowly returning. Burnham leaves, and a manifestation of Gray jokingly tells Adira that her bowing could use some work. He notes Adira did not tell Burnham that she can still see him. They both admit they do not know why or how she can still see him, and he helps her practice her bowing as Discovery flies away.