Hoid introduces the subject of his story, a girl named Glorf whom everyone calls Tress . He describes her home island, Diggen's Point , as a dismal place, and tells of the dangers of the spores that fall from the Verdant Lunagree . Despite her surroundings, Tress likes it there on the island, and is happy there.
Hoid continues to describe Tress as completely ordinary, but thoughtful and polite. She loves cups, and enjoys the story that each cup seems to tell. Tress goes up to the duke's mansion to visit Charlie , the duke's son. Charlie pretends to be a simple groundskeeper, but as always, does an unconvincing job of it. Tress gives him a pie, and shows him her newest cup. He entertains her with his stories and ideas, and in turn asks her about her day, wanting to know every detail.
Charlie rests his hand on Tress's hand. Tress wants to say something romantic, but fumbles with her words. He smiles at her, but Tress glimpses his father watching through the window. She leaves shortly thereafter. The next morning, she hears news that the duke and his son are leaving the island that very day.
Tress learns that Charlie is to be married off to a princess on a distant island. She doesn't act out, but instead goes about her daily business, distracted by her thoughts of Charlie. Charlie finds her and speaks to her, and Tress says she wishes he didn't have to go marry someone else. Charlie promises her that he won't marry any of the princesses, that he'll be so boring that none of them can stand him. He promises to send her a cup at every stop, after he gets the resident princess to reject him. Charlie is summoned by his father, and he gets on a ship with his family and departs. In the following months, Tress receives several cups and letters from Charlie, describing how he offended or grossed out various marriage candidates. But eventually, the cups stop coming. A year after Charlie's departure, word arrives at Diggen's Point that the duke is returning with his wife, heir, and daughter-in-law .
Tress sits on her porch, crying and regretting not having said more to Charlie before he left. The duke and his family arrive, but his heir is clearly not Charlie. He announces that due to an unfortunate accident, he had to adopt his nephew Dirk as his heir. The duke announces a party, and Tress finds Flik , one of the duke's servants. Flik explains that Charlie tried hard to put off all the princesses, but the duke figured out what he was doing and sent him to the Midnight Sea , where he was captured by the Sorceress . Tress learns from the duke's steward, Brunswick , that they'd received a ransom letter from the Sorceress, which the duke declared to be a trick. After two months of lethargically going about her daily tasks, Tress decides to go out and save Charlie on her own.
Tress tells her parents that she plans to rescue Charlie. Lem agrees to let her go and convinces Ulba that Tress is practical and smart enough that her rescue mission must be necessary. Tress and Ulba then observe how the docks and the Inspector operate. After two weeks of reconnaissance, Tress comes up with a plan that could work if not for Brick , Gremmy , and Sor .
Lem goes to Brick's Tavern and plays darts with Jule , Rod , and others. While playing darts, he asks questions that subtly indicate he needs the help of Brick, Gremmy, and Sor. Word gets around, and the next day the three show up to help Tress. Around a week later, the Oot's Dream docks at Diggen's Point and the captain demands an inspection of the cargo he's buying. Disguised as an inspector, Tress examines the barrels of ale. She finds Gret hiding in a barrel and demands passage on the Oot's Dream, using her authority as the inspector to secure a berth.
As the Oot's Dream sails away from Diggen's Point, Tress reflects on how her escape succeeded. The captain joins her on the quarterdeck as she watches the sea. Tress excuses herself to her cabin to get away from the captain and drinks some water that had been poisoned by his order. She begins to hallucinate as she falls unconscious.
Tress wakes up locked in a cage in the hold of the Oot's Dream . She meets Huck , who tells her that the crew are smugglers and had poisoned her because they thought she was trying to turn them in. Huck reveals that he is a talking rat. He explains that was caught eating rations and had to show that he could talk to not be killed. As Tress tells him that she left Diggen's Point to rescue someone, a cannonball is shot through the hull of the ship.
Verdant spores slowly begin to flow through the hole and contact the water the cannonball delivered, exploding into a mass of vines. Dorp comes down to patch the hole with roseite spores then kills any remaining spores with silver . Tress calls for him to bring her above deck, thinking that the attacking ship must be a royal ship and so would stop firing if they see her dressed as a royal inspector.
Tress is led up above and sees the Crow's Song firing on them. Dorp gets permission from the captain to try Tress's plan, claiming it was his own. Tress tries to get the attention of the Crow's Song , but they keep attacking. Tress is taken back to the hold because of this failing. As the seethe stops, another cannonball goes straight through the hull, not exploding its payload of water. Tress tries to leave through the new hole, but Dorp tackles her and tries to take her jacket. Tress knocks him out with her pewter cup. She then frees Huck, who now gives his name, and brings him along as she exits the Oot's Dream to walk across the spores to the attacking ship.
Tress, carrying Huck, walks cautiously across the stilled spores to the Crow's Song . Other sailors from the Oot's Dream also try, but die midway either due to haste or being shot by Captain Crow . Upon reaching the Crow's Song , Tress tries to climb it but fails. She then flings a bit of saliva onto the spores to grow some vines. She climbs the vines up to a porthole and watches the Oot's Dream sink as the seethe starts again. Crow shoots two of the three survivors. After fifteen minutes of clinging to the side of the ship, Tress is thrown a rope and pulled up. She is told that the Crow's Song is a pirate ship. Crow threatens to throw her overboard as they have no use for an inspector. Tress begins scrubbing the deck to prove that she is useful and continues scrubbing until she eventually falls asleep.
Tress wakes, and her first thought is of Charlie; she rues how naive she was to undertake this quest, but she still thinks of him trapped and alone somewhere. First watch mess is announced, and Laggart explains second watch will be next. The captain declares that Tress is third watch. When this is never called, Tress suspects this was a kind of joke. She notes the crew is somber. She recognizes Hoid after he helps her with a bucket of water for the deck, but he talks nonsense. The crew looks normal enough based on her experience that she wonders how they wound up as pirates. Hoid reveals to the reader that he was cursed by the Sorceress and lost his senses. Huck returns and confirms that they are sewing their first pirate flag and are new at it. She wonders if this is why they are cheerless.
The narrator explains that the Crow's Song is roughly twice the size and crew capacity of the Oot's Dream and has two guns rather than one. The convention of referring to most crew as Doug is established. She asks Doug where the toilet is and otherwise explores the ship. She comes upon Fort (the quartermaster) and Ann (the carpenter) inspecting a cannonball and whether any other defective ones were found. Fort communicates through a board in which words appear. They describe the destruction of the Oot's Dream as an accident, and "not the kind of piracy we signed up for." Ann says at least they aren't being conscripted. Huck explains that the whole crew is culpable of murders committed during piracy due to the felony murder law. He also overheard that the quartermaster is deaf. Huck starts telling her about a deaf human he once met, but Tress reminds him that the crew on the last ship caged him after learning he could talk. Fort notices them sneaking around, and he calls her over.
Fort and Tress are introduced to each other and discuss the fact that Tress is now a pirate, or at least shouldn't say she's not if she doesn't want to get thrown overboard. Fort offers her food, and she eats what he gives her (though it is not very good). She asks about his communication board and he explains he traded for it from a wizard (who the narrator explains was an off-worlder from Nalthis ). He cautions that it only works for him so she shouldn't even think about stealing it. She protests he's been so kind. He responds that it's not kindness, but a trade. Salay arrives and gives Fort four gold earrings she'd won at cards in trade for a pocket watch she'd wanted for a while. Fort tells Tress to come back after dinner for more scraps. Hoid arrives and also has some scraps. He clarifies for the reader the senses the Sorceress cursed away are taste (in the abstract), decorum, purpose, and self and that the important crew members to remember are Crow, Laggart, Fort, Ann, Salay , and Ulaam .
Tress returns to deck scrubbing and talks to Huck about some of the things she learned from ships visiting the Rock. As her work brings her near the cannon, a Doug asks her to help him carry what turns out to be zephyr spores. He mentions that Weev used to do all spore work, as ship's sprouter, but he was "let off" because he wouldn't agree to become a pirate. Tress is tasked with putting the zephyr spores, which produce bursts of air when activated, into charge-sized pouches. Tress accepts, since she's new on the ship, and dons the goggles and mask.
The blue zephyr spores fascinate Tress, particularly because they could kill her. She dismisses Huck so he won't be in danger and thinks of how facing these hazards and drudgery will help her help Charlie. She notices the large barrel has a false bottom (from her weeks figuring a way to be smuggled off the Rock.) Inside she finds a hidden cannonball. She realizes this is how Laggart hid the "defective" cannonball that sank the Oot's Dream , and is chilled to realize he hid this from the crew. Ann arrives, and Tress notes how she is besotted with the cannon and wonders if she's in cahoots with Laggart. Ann explains that in addition to ship's carpenter, she's assistant cannon master. Tress comments the crew seems to be adjusting well to being pirates. Ann tells how Crow said with the war coming, they'd either all wind up fighting for the king or they could strike out on their own doing an "noble and important duty" of stealing from the rich and selling to the poor. Ann expresses regret over becoming deadrunners on their first outing. Tress is not familiar with this term, so Ann explains it. Tress believes that Ann was not part of Laggart's plot. However, the captain probably was, because she left that survivor in the lifeboat to spread the word of their battle. Absorbed in thought, Tress accidentally scratches her nose and feels her face explode.