Notorious

Twelve-year-old Keenan Cardinal is recovering from tuberculosis on Centerlight Island, a small island in Michigan's St. Clair River where the U.S.-Canada border zigzags through the middle of town. Keenan's parents are divorced: his mother and stepfather, Klaus, teach at international schools abroad, while his father, Brad Cardinal, lives on the island. After contracting TB overseas, Keenan is convalescing in Brad's backyard, confined to a lawn chair on doctor's orders, bored and weak, hoping for clearance to return to Shanghai.

One afternoon, ZeeBee (Zarabeth) Tice, a Canadian islander whose father, Officer Darryl Tice, works for the Canadian Border Service, emerges through the backyard hedge with a blond cocker spaniel she dismissively calls Barney Two. She explains that the original Barney, a massive mixed-breed dog, was "murdered," though he was fifteen when he died. ZeeBee insists everyone on Centerlight hated Barney for his destructive behavior, making the entire island a pool of suspects. She also recounts the island's Prohibition-era history as a smuggling route and tells Keenan that her house once belonged to Tommy-Gun Ferguson, a notorious gangster who allegedly converted his fortune into gold and hid it on the island before his arrest. Keenan is skeptical of both the murder claim and the treasure legend but enjoys ZeeBee's company.

ZeeBee is the only Canadian child her age on the island and takes a ferry to school on the Ontario mainland, which isolates her from both communities. Keenan becomes her sole friend. She visits daily with gifts and gangster trivia and confides that someone has been watching her house at night, though her father dismisses her concerns.

When Dr. Sobel clears Keenan to leave the yard, Brad signs him up for training at Island Fitness with Bryce Bergstrom, a twenty-two-year-old former amateur MMA fighter with a jagged scar on his forearm, which Bryce attributes to an opponent's fingernails. Keenan's tae kwon do background gives him a foundation for kickboxing, but he cannot land the flying kick he once mastered. ZeeBee lends him her brother Wayne's bicycle and tours him through the island's gangster landmarks, deepening his sense that the criminal history may be more than legend.

When school begins, Keenan enrolls at Centerlight Middle School and quickly befriends classmates Ronnie Lindahl and Joey Cobretti, who consider ZeeBee weird for her gangster obsession and her insistence that Barney was murdered. ZeeBee, watching Keenan play with his new friends from afar, feels replaced and retreats.

Ronnie hosts a gathering that spirals out of control and migrates to the lighthouse, where kids break in. When someone accidentally disables the beacon, Keenan restores it using a reboot technique he learned from Officer Tice. Police approach and everyone flees, but Keenan, injured in the scramble, is left behind. Officer Tice finds him and drives him home. ZeeBee is furious, viewing the incident as proof that Keenan chose the kids who always exclude her. She confronts him, storms out, and cuts off all contact.

While biking through woods on the Canadian side, Keenan stumbles upon a clearing littered with animal corpses surrounding pieces of dried, poisoned meat. He deduces that someone used poisoned bait to kill Barney, and the small creatures died from scavenging what the dog left behind. Browsing ZeeBee's Instagram, he sees the original Barney's extraordinary size and wild energy, making the murder theory fully credible. He launches a solo investigation, searching newspaper archives and learning that Barney destroyed a neighbor's Porsche and porch just two days before his death with no signs of decline. He discovers that a community meeting occurred on April 17 at the hall directly across the street from ZeeBee's house, photographs the sign-in sheets, and cross-references attendees with people who filed complaints against Barney to compile a list of nine suspects.

Keenan visits suspects under various pretexts. He questions Michael Farnsworth, the islander whose property Barney damaged, and is thrown out. He visits the Quayle sisters, two elderly Canadian gardeners whose prize roses Barney repeatedly destroyed, and notes that they keep poison on their shelf. He interviews Peter Tolenski, a writer he met through Bryce who is researching Centerlight's Prohibition history and has published The Fortune Hunters, a book about treasure seekers. ZeeBee, still estranged, spies on Keenan and sees him visiting people who had conflicts with Barney. She initially thinks he is conspiring with her enemies, then realizes he has been investigating the murder on her behalf.

She rides to his house to apologize. Keenan leads her to the clearing and shows her the evidence. ZeeBee breaks down crying, finally confirmed in her belief. They reconcile and set up investigation headquarters in Keenan's bedroom, where ZeeBee coins the term "Notorious Nine" for the suspect group. They watch a video of the April 17 meeting and time each suspect's absence from the room, narrowing the list to five but reaching no conclusion.

The investigation escalates when the Tice house is burglarized while the family is away. Every drawer is dumped and closets ransacked, but nothing is stolen. ZeeBee argues the intruders were searching for Tommy-Gun Ferguson's gold. Keenan proposes a crucial reframing: Barney was killed not out of revenge but because his fierce presence made the house inaccessible to treasure hunters. The real killer is a treasure hunter, not simply a Barney-hater.

During the cleanup, Keenan notices a small carpet sitting in a custom-built recess flush with the floor, marked by a faded dot created by a sunbeam passing through a stained-glass window. He holds the carpet against an antique map of the island hanging on the wall and finds they match in size. Placing the map in the floor recess, they wait for the afternoon sun, which projects a dot onto a location near the lighthouse along the border. They calculate the gold should be buried roughly 325 feet from the lighthouse.

After midnight, Keenan and ZeeBee ride to the site with shovels, Barney Two running alongside. They navigate by compass into the dark woods. Ronnie and Joey startle them along the way, having come to set off firecrackers, but Keenan bores them away with fake mathematical explanations. At the calculated spot, they dig until Barney Two's claws click against metal. They uncover a brass-clad steamer trunk packed with dozens of gold bars. Tommy-Gun Ferguson's legendary fortune is real.

Tolenski and Bryce emerge from the darkness and order them to step away. Bryce confesses he poisoned Barney, revealing that his forearm scar is a bite from the original dog, not an MMA injury. Tolenski stayed at the community meeting as an alibi while Bryce planted the poisoned meat. ZeeBee attacks Bryce, who shoves her down. Barney Two leaps onto Bryce and bites his scarred arm. Bryce shakes the dog free and raises a gold bar to crush him. At that moment, Ronnie and Joey's firecrackers explode through the woods, and Keenan executes the flying tae kwon do kick he has failed to land since his illness, driving his foot into the gold bar and knocking Bryce unconscious. ZeeBee tackles Tolenski, and Ronnie and Joey pile on. Officer Tice, drawn by the disturbance, arrives and arrests Tolenski.

Bryce and Tolenski are charged with attempted assault, child endangerment, the break-in, and animal cruelty. Keenan is treated for two fractured metatarsals. The gold totals 1,320 pounds, worth approximately twenty-six million dollars. A survey confirms the trunk sat exactly on the border, prompting competing international claims, though both countries agree to allocate six million dollars to repair the lighthouse. ZeeBee's credibility is fully restored: Her claims about the murder, the gold, and the surveillance all proved correct. The island kids who once mocked her invite her to social gatherings. ZeeBee finally embraces Barney Two as simply "Barney," declaring him a hero. She and Keenan hold a small funeral for the woodland animals killed by the poisoned meat, burying them beside old Barney's grave. Keenan decides to stay on Centerlight permanently with his father, recognizing that after years as a spectator in exotic cities, he has found a real home.