The Leopard (harry Hole, #8)

The novel opens with a horrific murder. An unnamed woman wakes in a dark room with a metal ball forced into her mouth. When she pulls a protruding wire in desperation, spring-loaded needles pierce her face and she drowns in her own blood. She is identified as Borgny Stem-Myhre, the first victim of a serial killer.

Detective Kaja Solness tracks Harry Hole to Hong Kong on orders from her boss, Gunnar Hagen, head of Oslo's Crime Squad. Harry has been living in squalor, smoking opium and hiding from gambling debts owed to a triad. He refuses to return until Kaja reveals his father, Olav Hole, is gravely ill.

Back in Oslo, Harry learns two victims, Borgny and a young lawyer named Charlotte Lolles, were both sedated with ketanome and killed by twenty-four symmetrical wounds to the mouth. He agrees to work the case secretly for Hagen, since the Ministry of Justice has granted investigative authority to Kripos, Norway's central crime unit, led by the ambitious Mikael Bellman. A third victim, Socialist member of parliament Marit Olsen, is abducted during her evening jog and pushed off a diving tower with a rope around her neck. The fall decapitates her.

Hagen sets up a covert unit of Harry, Kaja, and forensics officer Bjørn Holm in a makeshift office beneath Police HQ. Mussels on the hanging rope trace to Lake Lyseren, where the team finds a disused ropery and confirms the rope was recently cut there. Harry recruits Katrine Bratt, a brilliant detective hospitalized at a psychiatric facility in Bergen, to run searches using a classified intelligence search engine.

Katrine discovers the crucial link: Three murder victims, a missing woman named Adele Vetlesen, and an Australian woman named Iska Peller all stayed at the Håvass cabin, a remote mountain lodge, on the same November night. A fourth victim, Elias Skog, is found drowned in his bathtub in Stavanger, glued to the bottom with Super Glue. At the cabin, Kaja discovers the guest-book page for that night has been torn out.

Harry travels to the Congo to trace Adele's supposed trip to Africa and learns someone else traveled under her name. In Goma, a Belgian arms dealer named Eddie Van Boorst shows Harry the murder weapon: a "Leopold's apple," a metal ball with twenty-four spring-loaded needles, originally designed as a torture device during King Leopold's colonial exploitation of the Congo. The team identifies the impostor as Juliana Verni from Leipzig, Germany, later found dead by the same method. They deduce the killer sent Juliana to create a false trail, then murdered her. A volcano expert links stones from the crime scenes to lava from Nyiragongo, an active volcano near Goma where Tony Leike, a well-known investor engaged to shipping heiress Lene Galtung, has mining interests.

Divers find Adele's body in Lake Lyseren. Tony voluntarily comes forward, claiming he was at the cabin. Harry discovers Tony's secret phone called Elias Skog days before Skog's murder. Harry obtains a warrant, but Bellman, tipped off by a mole, arrests Tony first. The arrest collapses when Tony produces alibis for at least two of the murders. Bellman coerces Harry into accepting public blame by threatening drug charges. Harry realizes the mole is Kaja, who has been in a secret affair with Bellman. She confesses and ends the relationship, and she and Harry begin a romantic relationship.

When Tony disappears, Harry devises a trap: Kaja will pose as Iska Peller at the Håvass cabin, with Kripos officers hidden nearby. An explosion triggers an avalanche that buries the cabin. Harry survives by breathing through a ski pole thrust up the chimney and firing his pistol to signal rescuers. He saves Kaja, but Jussi Kolkka, the Kripos officer stationed inside as protection, dies.

DNA evidence confirms Tony had sex with Adele at the cabin. Harry pieces together the motive: The unknown "eighth guest" who brought Adele witnessed Tony with his girlfriend and was consumed by jealous rage. This mirrors Tony's youth, when he attacked a boy near Lake Lyseren and cut off the boy's tongue over a girl. Harry visits the Snowman, a terminally ill serial killer he previously caught, who tells him the killer is hiding in plain sight. Afterward, at a bar, Harry sees a bottle of Bristol Cream sherry and the pieces click: Sigurd Altman, the nurse caring for Olav at the hospital, is the killer. Altman changed his name from Ole S. Hansen, the boy Tony maimed years ago. His fingerprints match those found on Tony's desk, and Altman is arrested.

The case turns again. While searching the mountains after the avalanche, Harry and Bellman had found a wrecked snowmobile with a body in a ravine, initially assumed to be Tony's. The body is now identified as Odd Utmo, a local recluse revealed to be Tony's biological father. Tony grew up under Utmo's abuse until his mother, Karen Leike, secretly sent him to live with his grandfather. Utmo murdered Karen, whose remains are found nearby. Tony tortured and killed his own father.

Bellman cuts a deal with Altman, who reveals he did not commit the murders but inadvertently triggered them. After witnessing Tony stab Adele to death, Altman was too frightened to go to the police. Instead, he sent blackmail letters to Tony in the names of other Håvass guests, hoping Tony would be caught when he killed again. Each murder prompted another letter, creating a chain. Altman goes free in exchange for testimony.

Harry confirms Tony is alive, having faked his death by cutting off his own finger and sending it to Harry as a taunt. Tony escapes to the Congo, and Lene, disguised with dyed hair, withdraws two million euros to join him. Harry and Kaja pursue them to Goma. Harry is ambushed and wakes with a Leopold's apple in his mouth, wired to a door so that anyone entering would trigger the needles. He slams his jaw against a wall nail to dislodge the device, escapes, and arms himself.

Tony takes Lene, handcuffed with a golden apple in her mouth, and a captured Kaja to the rim of Nyiragongo. He forces Lene to sign a marriage contract granting him inheritance rights and prepares to push both women into the lava. Harry arrives with a high-caliber rifle and fires a single shot across the crater, killing both Lene and Tony. Kaja survives, and they dispose of both bodies in the volcano.

On the flight home, Harry learns his father has died. At Olav's funeral, he briefly sees Rakel, his former partner, and her son Oleg. He visits Rakel and tells her he needs to repair himself before they can try again, then ends his relationship with Kaja.

In a final visit to the Snowman's hospital room, Harry leaves a coded message implying he has placed a fatal dose of ketanome in the bathroom, fulfilling for his worst enemy the act of euthanasia he could not perform for his own father. The epilogue finds Harry back in Hong Kong, working as a debt collector, sober, with two unopened letters in his pocket and a tip on a promising horse at the Happy Valley racecourse.