In a log entry set to be automatically transmitted if and when USS Discovery is ever found, Michael Burnham describes her year spent apart from the ship in the future, as well as the nature of the Burn and the collapse of the Federation. She explains that she became a courier in order to search for clues about what caused the Burn, look for ways to reunite the Federation and search for Discovery.
Burnham apparently spends some time traveling in a small craft on her own, but also shows she works with and is friends with Cleveland Booker. Burnham reveals she has accepted the fact that she may never see her former crewmates again — but her log is interrupted when she receives a notification that Discovery has been detected.
Burnham and Saru catch up while walking through the corridors. Burnham says she sent a transmission to Terralysium, but that the response took months to arrive and the residents had no knowledge of her mother. Burnham also promised to give Booker some of Discovery‘s dilithium, which Saru promises to honor.
She reveals she discovered a twelve-year-old transmission on an obsolete Starfleet channel. The message from Admiral Senna Tal says he awaits any remaining Starfleet personnel on Earth. Burnham proposes using the spore drive to jump to Earth, which is distant enough that she was unable to journey that far. Stamets asks whether he should prepare for a jump, but looks back and forth between Saru and Burnham, unsure who is in command. Saru notes the two of them must decide who will become captain, but Burnham declines and tells Saru he should be in command and says she is unsure if she was ever right for such a position. Saru sits in the captain’s chair and tells the crew to prepare for their mission, prompting the crew to respond “Aye, captain.”
Outside Discovery, various work pods and DOT-7s repair the ship’s hull. Inside, Ensign Sylvia Tilly looks at a memorial wall with Starfleet insignia. She tells Burnham she has not had time to grieve those who died or were left behind in the past, including her mother, cousins and other family. They lived their lives and died centuries ago, she says tearfully. She hopes to find something familiar on Earth to ground her, such as the Gateway Arch, the Great Pyramid, or homemade hummingbird cake. “Cake is eternal,” Burnham responds lightly.
Tilly says she knows Burnham had let the Discovery crew go, which Burnham does not deny, and the two embrace. Tilly says Burnham also seems “lighter somehow.”
Booker beams aboard Discovery and is surprised to find not Keyla Detmer or Tilly at the controls but Georgiou, about whom he says Burnham warned him. She interrogates Booker about whether his relationship with Burnham is romantic; he initially denies it, then refuses to discuss the matter with her further. Georgiou says she is no longer certain the Burnham of 3189 will still be “earnest and doing the right thing.”
Later, Burnham extracts some dilithium from Discovery‘s core. The amount of dilithium amazes Book, who says it could run as many as a dozen sectors. Burnham reveals the ship feels “familiar” but “far away,” and Booker tells her she does not necessarily owe the Discovery crew anything. He also warns that their stash of dilithium will make the ship a target. She offers to bring Booker with them to Earth, where she says he would be safe from those who he has angered. He says he believes in his conservation work and does not wish to give it up, but she says Discovery needs his help to mask their dilithium stores.
In the ready room, Saru tells Burnham he is uncertain about trusting her judgment and that while he is grateful she supported his captaincy, he was surprised at her lack of interest in the job. Burnham says she adapted to the unexpected new future in which they found themselves. Booker’s ship is brought into the shuttlebay, where the dilithium is loaded and it is cloaked. Saru states that Book will not be permitted to board his ship until they reach Earth, and the dilithium is safely removed. Using the spore drive, Discovery jumps to the Sol system, near Saturn. Book, impressed, says Burnham did not tell him about “the spinning part.”
As Discovery approaches Earth, a system of advanced force field-generating arrays activates, creating an impenetrable barrier around the planet. Two non-Starfleet vessels approach as Discovery goes to red alert. They are hailed by Captain Ndoye of the United Earth Defense Force, who finds their viewscreen method of communication “quaint.” She informs Saru that Discovery has violated regulations C1922 and F031 of the United Earth charter and orders the ship to leave immediately.
Saru presents Discovery‘s cover story – that it was on a long-term classified scientific expedition when it was effectively stranded by the Burn, and that they are the descendants of the original crew. Ndoye notes the ship’s design and metallurgy indicate it was built between the 23rd and 25th centuries and expresses skepticism that so old a ship would still be in service. Burnham and Book, both wearing civilian clothes, quietly leave the bridge. Ndoye insists the ship be inspected, and abruptly beams her inspectors in across the ship, startling the Discovery crew.
In Burnham’s quarters, she and Booker dress in Starfleet uniforms so as to not to arouse suspicion, though Booker complains about the livery. It is “just a uniform,” Burnham responds. In the corridor, she encounters Georgiou, who has also dressed in a Starfleet uniform, albeit with an admiral’s rank. She notes Burnham does not appear to be thrilled to be back in uniform and speculates she grew used to living by her own rules, which allowed Burnham to discover who she really was.
In the ready room, Saru tells Ndoye he was perplexed by Earth’s gruff welcome. She replies that Earth was built to be self-sustainable following the Burn even as raiders tried to seize their remaining dilithium. She says the raiders’ current leader is a “relentless” man named Wen. Ndoye tells them the Federation and Starfleet left earth a century prior, having left for an unknown destination. She says many of the ships destroyed in the Burn were Federation, and that many felt if it was an attack and could happen again that their presence on Earth made it a target. Saru asks if that means that Earth is no longer a part of the Federation, to which Ndoye replies “we can take care of ourselves”. Burnham asks about the message from Senna Tal, which was sent twelve years ago; Ndoye’s records show he died on an outbound ship two years before.
In engineering, United Earth inspectors look over the equipment, annoying the crew. Adira, a young officer, questions why the spore cube is connected to Discovery‘s bridge controls. Stamets explains that he uses the cube for controlled spore reactions, which requires coordination with the bridge. Adira responds that the ship is “practically a museum.” She tell Stamets she is just sixteen years old, but another inspector cautions her not to engage the Discovery crew. Suddenly, the ship sounds red alert.
Five vessels approach – Wen’s ships, Ndoye warns. Saru answers Wen’s hail, and the helmeted raider tells them to surrender their dilithium immediately, unconvinced that the ship has none. Ndoye orders Discovery to leave Earth and they will deal with Wen, but she and her inspectors unexpectedly find themselves unable to beam away.
Burnham finds Booker in the ship’s mess, where he has been unknowingly drinking synthehol. She says she has a plan but that she has not gotten permission from Saru.
In engineering, Tilly and Stamets find an unknown device tapped into their systems inside a console. It has tapped into Discovery‘s deflector system to block the inspectors’ transporters and will take hours to disable safely. The two quickly grow suspicious of Adira, who had been examined that console earlier and was suspiciously knowledgeable of their 900-year-old starship systems. They are confused as to why she would trap her own people on board, but Stamets speculates she was trying to buy time for something.
Burnham and Booker leave on his ship, along with Discovery‘s supply of dilithium. Saru is angry but realizes Burnham must have a plan. Ndoye orders her ships to target the raider vessels, saying Wen cannot be allowed to obtain the dilithium. On his ship, Booker says the raider ships are much less powerful than those he is used to. As Grudge lounges nearby, Burnham and Booker discuss strategy in a shorthand that highlights their familiarity and history working together. Wen hails them, and they banter over the dilithium that they are holding on the ship. Burnham tells Wen they will beam the dilithium over if he agrees to leave Earth’s orbit immediately.
Saru places Discovery in the United Earth ships’ line of fire in order to protect Burnham. The two quantum torpedoes completely collapse Discovery‘s shields and cause explosions on the bridge, but Saru’s sacrifice has only briefly delayed a battle. Wen tells Burnham and Booker he will lower his shields to allow the dilithium to be beamed aboard. As tensions rise, Joann Owosekun reports that Booker’s ship has cloaked and Gen Rhys says the raiders are powering down weapons.
The turbolift doors open to reveal Burnham and Booker holding Wen captive. They beamed him off his ship and onto Discovery, and the raiders are unwilling to fire on them with Wen held hostage. Burnham says it is time for Ndoye and Wen to talk.
Wen complains that Earth hoards its dilithium without using it, leaving others to suffer. Burnham urges them to speak face-to-face. Wen is uncooperative, but an impatient Georgiou attacks him and removes his helmet, revealing him to be Human.
Meanwhile, Stamets finds Adira in a Jefferies tube, studying the ship. He asks why she sabotaged Discovery, and she explains that she found the ship’s technology suspicious. “Explain it to me, or I’ll report you”, she said… although Stamets says that if she were to report them, she would have done it already. He explains that Discovery uses the spore drive as an alternate form of faster-than-light travel and that he is the system’s unique Human navigator. Stamets reveals Discovery is from the year 2258 and demands Adira reveal her secret as well. Adira explains she became an inspector in the hopes of finding a Federation starship and that she wishes to accompany Discovery on its mission. She says she knows Senna Tal.
In the ready room, Burnham notes Wen’s vessel is crowded and broken down. Wen reveals he is from an old research colony on Titan that became independent from Earth a century ago but was devastated by an accident at its liquid hydrocarbon research facility that destroyed a third of the habitats, ruined their tillable soil, and left them without long-range communications. He says the first ship sent to Earth seeking help was destroyed and they knew they were on their own. Ndoye says Earth was unaware of Titan’s troubles. The Starfleet officers propose a trade, with Earth providing relief and Titan sharing its research findings.
Ndoye subsequently praises Saru’s handling of Wen and invited Discovery‘s crew to visit the surface. She also has authorized Adira to remain aboard Discovery, and wishes them luck in searching for Starfleet. Saru says Stamets told him Adira knows how to find Tal. “I am Admiral Tal,” Adira reveals.
Saru later tells Burnham that Adira, though Human, was joined with a Trill symbiont. Burnham said she has seen Trills at the exchanges but was unaware that they carried symbionts. Saru says the Sphere data indicates the symbionts are sentient, benevolent and long-lived, transitioning between hosts who can access prior hosts’ memories. However, Adira has some trouble accessing Tal’s memories, possibly because she is Human, not Trill.
Burnham admits she should have informed Saru of her plan beforehand. She adds that she would be proud to serve as his first officer, but that her year alone in the future meant she let go over certain things on Discovery and she will need time to “find her way back to them.” Saru says he will trust her to grow through her change.
Burnham bids farewell for now to Booker. He says she owes him, though Burnham retorts that she provided him with dilithium and life in a new quadrant.
On the bridge, Burnham finds Saru watching an image of the building that used to house Starfleet Academy on the viewscreen. The rest of the bridge crew has gone to the surface for a visit, but Burnham says she will admire the view from Discovery alongside Saru. On the surface, Tilly, Owosekun, Detmer, Rhys, Nilsson, and Bryce visit a tree many of them used to study under at the academy, now grown into an enormous round trunk. Rhys notes they have now stood in the same spot 930 years apart. Saru hails Tilly, who begs for five more minutes on the planet, a request Saru grants.