Clyden wakes Bortus with a discussion about his work-life balance. Clyden is feeling neglected. Bortus gets up to start his shift. Clyden consoles himself with "depression food" which is actualized by the computer as Rocky Road ice cream. He eats the ice cream watching The Sound of Music and Bortus leaves.
Malloy and LaMarr complains about the boringness of their current task, star-mapping. Bortus joins the bridge crew but doesn't want to talk about why he doesn't want to be in his quarters
Isaac notices a large object in space. Mercer orders The Orville to intercept. It turns out to be a gigantic ship, drifting in space, heading towards a star. It is made of an unknown alloy and appears to be two thousand years old. Mercer decides to take a shuttle over.
Yaphit is in sick bay with Dr. Finn again, complaining of malaise and trying to date the doctor.
Mercer, Grayson, Isaac, Kitan, and Doctor Finn take the shuttle to the unknown ship. Kitan uses her super strength to open the ship's air lock. As they enter, crossing a large catwalk with a huge drop on either side, Dr. Finn confesses to Isaac that she is afraid of heights. Once across, Kitan again opens the hatch and the away team enters a simulated outdoor environment. Dr. Finn identifies it as the biggest bio-ship anyone has ever seen. Isaac detects millions of life forms on board.
It is discovered that the away team is cut off from communicating with the Orville because of the ship's hull. The away team splits up to explore the ship. Isaac asks Mercer about his relationship with Grayson. Dr. Finn asks Isaac about how Kaylons procreate.
They find a cabin and Isaac detects three life forms. When Mercer tries to introduce himself, the woman slams the door. When he knocks again, a man answers and tries to shoot them. Isaac stuns him with a phaser. Mercer tries to talk to the woman about aid or evacuation but she doesn't understand him. Her son appears and Isaac deduces the people do not know they are on a space craft. The son, Tomilin, tells them to come with him.
Kitan and Grayson are scouting and having a chat about the men in their lives. They are approached by a black armored vehicle and two uniformed men jump out, demanding their identification. They shoot Kitan who tumbles down the hill and then knock Grayson out. Leaving Kitan at the bottom of the hill, they drag Grayson away.
Mercer's team follows Tomilin into the woods where he explains that he belongs to a group who have begun to question the scripture of their organized faith. He takes them to a meeting hall of Reformers.
On board the Orville, a distress call is received and Bortus makes the decision to lend aid, leaving the away team without back up until they can return.
At the Reformers meeting, Mercer and his team are learning about the structure of the society aboard the ship. Mercer doesn't enjoy the food they are served. Kitan makes contact to let them know she's been shot and Grayson has been taken. They set out to find her.
Grayson wakes up in the back of a transport in a city where Hamelac is preaching the word of Durall. He throws a Reformer into the mob where they beat him, possibly to death.
Grayson is brought in to Hamelac's office to be questioned and she asks why he incited the mob to kill the Reformer. He claims to be doing the word of Durall.
Mercer and Finn find Kitan and Finn removes the bullets from her chest and repairs the damage in front of Tomilin. When she tells them about the uniformed men, Tomilin identifies them as Enforcers who would have taken her to the city.
Mercer send Isaac to contact the Orville for reinforcement but Isaac finds the ship gone.
The Orville takes on the Krill ship in battle and LaMarr manages to disable the enemy's engines however they have sustained damage and they won't be able to get underway for an hour.
Mercer, Finn, Kitan, and Tomilin launch a rescue in the city to save Grayson. Hamelac tortures her for information with a pain-inducing truth serum. Kitan rips the doors off of their hinges and Dr. Finn administers the antidote. Hamelac refuses to believe their story about the ship's imminent demise. They give up trying to convince him, stun him, and leave.
The Reformers take the away team to another ship hatch and Isaac is able to open it. It opens to a lift and they take it to the ship's bridge where they access a recording by the ship's captain, Durall, explaining that the ship was meant to last three generations, long enough to reach the next planet from their remote homeworld. Damage from an ion storm knocked out their engines and the ship had been drifting ever since. Isaac identifies the engine issue and says they can repair it in 24 hrs. He also discovers that the ship has a retractable hull and Mercer orders him to show the inhabitants night for the first time in 2000 years.
The Orville returns to retrieve the away team and Mercer explains that the Union will send a team to teach the inhabitants how to pilot their own ship.