The London Eye Mystery (2007), by Siobhan Dowd, is a novel for young readers about a boy named Ted who teams up with his sister to figure out how their cousin disappeared while riding a giant Ferris wheel.

The novel was nominated for a Carnegie Medal, was listed as a 2008 Booklist Children’s Editors’ Choice title, and a School Library Journal Best Book of 2008. It was also shortlisted for many English awards, including the Red House Children’s Book Award, the Doncaster Book Award, and more. An activist for literacy, Dowd founded or worked for programs that support children’s rights, reading in under-served communities, and the rights of writers worldwide.

The London Eye Mystery has a Lexile rating of 640L, suitable for 4th grade and above. The ebook version of the original 2008 edition forms the basis for this study guide.

Content Warning: In the source text’s implicit discussions of autism, the author uses the term “high-functioning” to describe the protagonist’s situation on the spectrum. Since the book’s publication, however, that term has fallen into disuse due to its potential insensitivity; this study guide reproduces the language only within direct quotes.

Plot Summary

Young Ted Spark lives with his father, Ben, his mother, Faith, and his big sister, Kat, in a small house in South London. Ted has trouble socializing and mentions that he has a “funny brain that runs on a different operating system” (4). He gets along poorly with Kat, who’s prone to impatience, but he has a powerfully logical mind, and his favorite pastime is studying the weather.

Ted’s Aunt Gloria and her son, Salim, arrive for a visit. Gloria is moving from Manchester, England, to New York to work as an art curator. She’s a bundle of energy and strong emotions, and she and her sister, Faith, were estranged for years. Ted’s father, a building-demolition expert, predicts disaster, but the family reunion goes smoothly. Salim is quiet and intelligent, and he and Ted become friends. Ted shares how his mind works, and Salim accepts him for the way he is without judgment.

Faith, Gloria, and the three kids go downtown to ride the London Eye, a giant Ferris wheel that takes half an hour to complete one loop. Salim takes pictures with his old-fashioned film camera; he hands the camera to Ted, who takes a shot of the Wheel. The ticket line is long, and Gloria and Faith wait in a coffee house while the kids stand in line. A stranger gives them a free ticket, and Salim uses it to go on the ride. When Salim’s passenger capsule returns from its slow revolution around the wheel, he’s gone. The family searches everywhere, but Salim has disappeared.

They report Salim’s disappearance to the police, and Gloria becomes distraught. Ted and Kat draw up their own list of theories about their cousin’s disappearance. To test whether Salim might have gotten past them under someone’s gown or coat, they try to sneak Ted around their parents while he hides under Kat’s big house robe, but their mother catches them easily and scolds them for being frivolous during the crisis.

Kat convinces their father to take them again to the London Eye. On the way, she slips into a chemist’s with Salim’s camera film for developing. They ride the Eye, and Kat tries to linger and get a second ride, but an attendant makes her leave. This experience rules out a theory that Salim hid on the capsule for a second go-round. On the way home, Kat retrieves the photos, but when the siblings examine them, nothing seems unusual.

Ted posits a ninth theory: Salim never entered the capsule at all. Kat insists she saw him enter and that she recognized him by his body language (something Ted would have trouble with interpreting). Inspector Detective Pearce visits and announces that a boy resembling Salim was seen boarding a train for Manchester, but no one there has heard from him. Salim’s father, Rashid, arrives; he and Gloria argue angrily, but they reconcile and agree to inform the media about Salim’s disappearance. They film a brief statement asking the public to send them any information on their son’s whereabouts.

Ted looks again at the photos and finds the face of the stranger who gave them the free ticket. Kat gets the photos enlarged: Just visible on the man’s T-shirt is a partial lettering that they deduce spells “Frontline Security.” Kat leaves without Ted to search for the stranger. Ted figures out where she went and follows her to a motorcycle exhibition at a downtown hall where the stranger—Christy—works security. They locate Christy and confront him, but he claims ignorance of Salim’s situation, distracts them, and disappears. They track him to the subway and follow him to a neighborhood, but he turns the tables and confronts them. He admits that he received the ticket from an unknown, dark-haired woman who asked him as a favor to give it to the children.

Ted and Kat return home, where their mother is livid about their unsanctioned wanderings. Ted continues to struggle with the mystery until he realizes that Salim escaped the capsule by switching clothes with someone else. He reasons that it was Salim’s friend, Marcus, who boarded the train for Manchester. Ted tries to tell his family, but no one listens, so he calls the police. They contact Marcus and learn that Ted’s theory is correct.

Marcus visits the Spark house. He explains that Salim didn’t want to go to New York, so Marcus dressed in a long wig and his sister’s pink jacket, handed a ticket to his brother Christy to give to Salim, and then switched costumes with Salim in the capsule while the other passengers turned away to face the souvenir-photo camera. Thus disguised, they eluded Ted and Kat and escaped.

Salim had second thoughts about moving to New York with Gloria. He likes Ted and Kat, and he didn’t want to hurt his mother, so he sent Marcus alone back to Manchester. Marcus found Salim’s phone in the pink jacket, but otherwise he’s seen nothing further of Salim.

Ted and Kat try to figure out where Salim went. From Marcus’s description of Salim in the capsule staring south and commenting on the skyscrapers he saw, Ted reasons that his cousin was looking at the Barracks, an abandoned public-housing high-rise. Salim likes tall buildings, and, on his way back to the Spark house, he must have stopped at the Barracks to take some pictures. There, he became trapped inside when Ben Spark locked up the place prior to its scheduled demolition.

Kat raises the alarm, and everyone hurries through the rain to the Barracks. Ben unlocks the building, and they find Salim on the top floor, hungry and cold but unharmed.

Salim agrees to give New York City a try, and he and Gloria fly to the United States. Ted and Kat bask in the respect they’ve earned and the love and closeness they’ve rekindled in their family by solving the mystery and saving Salim’s life.