Anna stands in her cabin aboard the Philadelphia Phoenix, rehearsing the speech she plans to give to the train’s passengers. Anna chose the Phoenix because of its connection to her family. Her grandfather founded Union Atlantic Railroad, which designed and produced its own cars and locomotives, including the Phoenix. The company passed down to Anna’s father. Anna’s mother designed the train’s interiors. Debuting in 1937, the Phoenix is important to Anna, and she’s chosen it to remind the others of what she’s lost.

Seamus, Anna’s accomplice, knocks and tells her that everyone is aboard. Burt, an experienced man who was the only person to send Anna and her mother condolences after Anna’s father’s death, is the conductor. The other train employees have been sent away and paid off. Seamus is interrupted by one of the passengers. Anna hears Lieutenant Colonel Jack Lapsford’s voice and thinks he’s entitled and pompous. Anna believes that Jack, Sal Lawrence, Kenneth Wentworth, Herb Pulaski, Edith Gerhardt, and Judd Dodge are evil and deserve to suffer. Anna wants to kill them, but she won’t.

Anna sees snow outside and worries that the weather will escalate and force the train to stop; any stoppage, even for 30 seconds, would ruin her plan. She puts on a red dress, red shoes, and red lipstick: an outfit fit for revenge. She wears her father’s train engine brooch. She tucks a knife into her thigh sheath beneath her dress. Anna thinks she looks beautiful, like her mother Margaret. Margaret had a distinct beauty, and Anna’s father, Arthur, was besotted with her. Their courtship was quick, and Anna’s brother, Tommy, was born eight months after their wedding, though the family escaped any scandal. Anna thought Margaret was uncommonly beautiful, like a movie star. Anna didn’t inherit Margaret’s looks, but her brother, Tommy, did. Anna had a charmed life until Tommy died, then her father, then her mother. Anna tries to focus on the present, on the black briefcase in her cabin and the people on the train whom she holds responsible for the destruction of her family.

Judd Dodge notes that the Phoenix still has 13 cars and an engine, just like he designed it back when he worked for Union Atlantic Railroad. Judd designed the locomotives to be sturdy, except for the one time he was told not to. Afterward, he quit and became a professor. He rereads the invitation he received: “I know what you did. If you don’t come, others will know, too” (22). Judd knows he must face this, and he prefers to handle the issue on a crowded train. He boards the train and is led to a first-class cabin. Judd appreciates the beauty of the Phoenix as he follows the porter. Judd finds a note on his pillow telling him to attend a cocktail party in the first-class lounge at eight o’clock. Judd wanders through the train, unnerved to find it empty. The observation car, which is made of glass with floor-to-ceiling windows, is also empty, which Judd finds strange, given its popularity.

Judd was always good at working with his hands, and he worked in factories when he was young. He was hired by Union Atlantic, where he hit it off with Arthur Matheson. Arthur asked him to make a train that moved like liquid mercury. Judd reflects back on his role in a horrible event, and he thinks the train ride is going to make him pay for his sins.

Herb Pulaski wears a fraying, once-nice suit and boards the train 20 minutes early. He wants people to think he belongs in first class. His invitation reads, “It will be to your financial benefit if you come” (34). Herb is eager to make a good impression on the anonymous host as he waits in the first-class lounge. Judd enters, and they each accuse each other of being behind the plot to bring them to the Phoenix. Previously, Judd designed the engines and train components, and Herb worked as a factory foreman to ensure the designs were built. Their paths crossed when Judd designed a train for the US Army that Herb thought was flawed. He confronted Judd, who claimed Arthur designed it, but Herb knew he was lying. Judd brought Herb into his plan and made Herb rich under unethical circumstances. Herb used the money to live lavishly and find a wife. Now, the money is gone, and his marriage is in jeopardy. Judd thinks the man who owns the Phoenix is the only one who could hatch this plot. Herb doesn’t want to think about the choice he made, about the people who died, including Tommy Matheson. They have no idea how they’re supposed to get home from Chicago; the trip is one-way.

Sally Lawrence’s invitation reads, “Remember the old you? I do” (39). Sally changed herself over the years, first dropping the nickname “Sal” and using her full name. Once she became wealthy, she went to a beauty parlor for a drastic makeover, lost weight, and dressed in expensive clothing. Though she seeks to look younger, Sally thinks she looks like a wealthy spinster. Sally packed heavily for the journey, prepared for anything.

Sally feels a rush of memories being aboard the Phoenix. Sally regrets entering a bar 12 years ago looking for something “primal,” which led to a man blackmailing her with photographs from that night. Sally went through with the man’s plan and became rich, but she regrets the deaths and the destruction of the Matheson family. Sally remembers being aboard the Phoenix for its inaugural trip. Sally drinks from her flask before going to the first-class lounge. She sees Judd and Herb, who call her Sal.

Edith Gerhardt sees herself in the mirror. Dressed all in gray with gray hair, she thinks she resembles the Grauer Geist, or the gray ghost that haunts her family’s old estate in Germany. The ghost supposedly appears before impending doom, and Edith wonders if her ghostly appearance is heralding her doom, or if she’s the messenger. Edith almost threw away her invitation until she saw the note that reads, “How much will you pay to keep your secret?” (45). Edith would pay anything, even though she spent most of her life poor and understands the value of money. She’s wealthy, but she lives frugally; she thinks wasting money is an American trait, and Edith clings to her German roots. She emigrated in 1936, not to avoid Hitler’s rise but because her husband and family died. She moved to the United States because she predicted the US would win the war. She got a job as a housekeeper for a wealthy Philadelphia family. She had to choose between her old country and her new country in 1942, and her choice made her rich. Edith knows her past is coming to haunt her. She goes to the first-class lounge and sees Judd, Herb, and Sally.

Lt. Col. Jack Lapsford is 72 and retired, but he likes to get things done. He wanders through the train and finds it empty, which concerns him. He knows why he’s aboard the train, as his invitation reads, “How does it feel to have blood on your hands?” (51). Someone knows what happened 12 years ago, when Jack was in Washington. He was approached by a man connected to a railroad company who encouraged Jack to give a military contract to a different company for sabotage. The man told Jack that the US needed more motivation for the war against Hitler and Nazi Germany, like the rush of support after Pearl Harbor. Jack agreed, as he callously thought the lives lost would be lost anyway, and getting American war-ready was more important. Jack doesn’t regret it, as he thinks regrets are for the weak. He finds Judd, Herb, Sally, and Edith in the lounge and wonders who’s brought them together.

Dante Wentworth knows who’s behind the invitations. His father, Kenneth, was invited, and his note reads, “You and I have unfinished business” (55). Dante stole the invitation, recognizing Anna’s handwriting. Dante’s father owns the Phoenix and is fascinated with trains, but Dante knows that trains will soon become obsolete. Dante hopes Anna isn’t upset that he stole his father’s invitation. He practices what to say to her to show that he genuinely missed her. Dante was an awkward youth, but he grew into his features and broke a few hearts, which he handled gently, except one. Dante sneaks into the lounge and counts five other people on the train. He studies them as they speak in hushed tones until they notice him. Dante tells them that his father isn’t behind this, but he knows who is, and no one but Dante will be happy to see that person.

Anna waits eagerly for eight o’clock. Seamus arrives and tells her that the fake employees and the fake passengers are gone. Anna tries to emotionally prepare herself as she sees five of the six people through a window. She thought any fondness she once felt would be gone, but she still has positive memories of Edith, who worked for her family and helped raise her, and Sal, who worked as her father’s secretary and whom Anna regarded as a sister figure. Anna only saw Judd and Herb at her father’s company Christmas parties. She liked Judd, who showed her magic tricks, but she disliked Herb, who once shamed her for being from a wealthy family. She only met Jack once at a dinner with her father, in which Jack pushed Arthur to accept a military contract. She doesn’t see Kenneth, whom she blames more than the others. She believes Kenneth hatched the plan to destroy her family. When the group stands and moves, she sees Dante. Seamus tells her that Kenneth isn’t here, but Dante is. Anna struggles to keep her memories of Dante suppressed.

Anna steadies herself and enters the lounge. She feels hatred for these people and suppresses her violent urges. She struggles to speak, feeling nervous. She forces herself to tell the group that they know who she is and why they’re here, but if they haven’t figured it out yet, they will soon. Anna visits a memory of when she went to live with her wealthy, widowed Aunt Henrietta, or Retta, after her parents’ deaths. Anna was 16. Retta didn’t want Anna, even slapping Anna to test Anna’s resolve. Retta told Anna that emotions made her weak; only unflinching resolve could demonstrate strength. Retta kept slapping Anna until Anna no longer flinched.

Anna pushes the memories away and tells the group that she has proof that they are responsible for the destruction of her family. She tells the story of what happened on June 17, 1942. A troop transport train left Philadelphia for Fort Benning, Georgia, with 200 soldiers aboard, including Tommy Matheson, who enlisted when he turned 18. The train’s locomotive was intentionally designed to explode, and it blew up outside Raleigh, North Carolina, killing 37 men, including Tommy. Immediately after, the blame fell on Anna’s father, Arthur. The authorities investigated and found incriminating documents before arresting Arthur. The papers and outside testimonies made Arthur seem like a Nazi sympathizer, but his case never went to trial. He was stabbed to death in jail 37 times, one for each life lost.

No one attended Arthur’s funeral except Anna, her mother, and Aunt Retta. Arthur’s reputation was destroyed, as Jack, Judd, Herb, Sal, and Edith testified against him. Arthur’s rail company’s price plummeted and was bought by Kenneth. Two months later, Anna’s mother took her for a picnic before her mother got back in the car and drove it into the river, dying by suicide.

Dante asks what Anna’s story about the train crash has to do with them, and Anna is uncertain if he is unaware of Kenneth’s role in the tragedy. Anna was unaware until Aunt Retta told her about the plot on her deathbed and promised Anna that she had proof.

Aunt Retta promised Anna that the proof—documents proving who was behind the explosion—would find Anna. Retta used her last words to implore Anna to get vengeance on those who ruined their family.

Anna outlines each person’s role in the destruction of her family: Jack falsely testified that Arthur approached him about building the train, Judd designed the doomed engine but showed Arthur a different set of plans, Herb oversaw the construction of the faulty train, Sally created false documents and memos to incriminate Arthur, and Edith hid documents suggesting that Arthur was a Nazi sympathizer in the Mathesons’ house. Anna tells Dante that his father orchestrated the explosion. He used the plan to tank the value of Union Atlantic and then buy it for cheap, paying off the others involved with the profits. They deny it, but Anna has evidence. She shows a copy of Judd’s original plans for the engine.

Judd believes Anna intends to kill them, but Anna reveals that she sent the evidence to the FBI office in Chicago along with the train’s intended arrival time. The group will be arrested, tried, and convicted for their crimes. Jack plans to get off at one of the stops, but when the train reaches Harrisburg, it passes through the station without stopping. Anna reveals the train is an express service with no stops. Judd confirms the locomotive can make it to Chicago without refueling. Jack notices the emergency brake and pulls it.