Billy Boyle Books in Order

A young Boston cop expecting a safe wartime posting lands in Blitz-era London instead, where Uncle Ike Eisenhower makes him a personal investigator. Sent to the Norwegian government in exile, Billy must find a spy before more people die.

Billy lands in Algeria with the first wave of the Allied invasion and steps into a mess of rival loyalties, black market theft, and murder. He has to untangle the killings while trying to save the British spy he loves.

Billy wakes in a Sicilian field hospital with amnesia, a mysterious embroidered handkerchief, and enemies closing in. As his memory returns, so does a dangerous mission involving murder, the Mafia, and the Allied invasion.

Sent to Northern Ireland after weapons vanish from a US Army depot, Billy must stop an IRA uprising that may be backed by Germany. The case forces him to question his own Irish loyalties as the bodies pile up.

In London, Billy investigates the murder of a Soviet security officer just as the Katyn massacre threatens to split the Allies. When evidence points toward his Polish friend Kaz, the case turns painfully personal.

Billy is sent to Italy to investigate the murders of two American officers, each left with a playing card. With Anzio looming and fear everywhere, he has to stop a killer who seems to be hunting up the chain of command.

A murdered American monsignor sends Billy into German-occupied Rome and the maze of Vatican politics. While tracking the killer, he also risks everything to find Diana Seaton, who has vanished on an undercover mission.

Back in England in 1944, Billy is pulled into two cases at once: a murder in a village under tight restrictions, and a Black soldier facing execution for a crime he likely did not commit. The book digs hard into racism in the wartime Army.

When a corpse washes ashore near the secret D-Day rehearsal at Slapton Sands, Billy and Kaz begin a murder case wrapped in wartime secrecy. Then disaster strikes, and the mystery widens inside an English country house full of buried grudges.

In the Solomons, Billy is sent to investigate a murder that could entangle PT skipper Jack Kennedy, still reeling from the loss of PT-109. The search unfolds under fire, among shifting identities and brutal Pacific warfare.

Billy is framed, busted to private, and offered one way out: parachute into occupied France before D-Day and investigate killings at an Allied safe house. He has almost no time, no safety net, and enemies on every side.

Billy and Kaz head to neutral Switzerland to probe Swiss banks handling looted Nazi gold, then stumble into murder and a wider conspiracy. Their mission becomes a dangerous mix of espionage, diplomacy, and moral reckoning.

A murder near the Normandy front pulls Billy, Kaz, and Big Mike into the secret world of the Ghost Army, whose fake tanks and radio tricks help fool the Germans. If Billy cannot solve the case quietly, the deception could collapse.

Billy and Kaz are ordered to let a traitor to the French Resistance keep running, because he is carrying fake Allied plans into occupied Paris. It is a tense chase through liberation politics, murder, and wartime deception.

Shaken after Paris, Billy and Kaz land in a secret British convalescent hospital where spies and broken operatives recover, or are kept from leaving. When two deaths suggest murder, Billy must investigate while barely holding himself together.

At a Soviet airbase in Ukraine, Billy is assigned to solve the murders of an American and a Soviet agent before a crucial Allied bombing plan unravels. Surrounded by mistrust, he finds help from the Night Witches, the famed Soviet women pilots.

Pulled from rest in Cairo, Billy is sent to German-occupied Crete to find a missing British operative. The mission carries him on to France, where resistance politics, collaborators, and the 442nd make it hard to tell ally from enemy.

While on leave in rural England, Billy is drawn into a murder tied to a long-lost plane crash and old local grudges. What begins as a quiet country puzzle opens onto wartime secrets much closer to Diana Seaton's world than Billy expects.

In post-Liberation Paris, Billy uncovers a shadowy network smuggling stolen art out of France. Following the trail puts him alongside unusual wartime allies and carries him into the deadly winter of the Battle of the Bulge.

Billy hopes for a quiet Christmas with Diana in southeast England, then the two find a dead American officer on the White Cliffs. The investigation leads from secret radio warfare to Yugoslavia, where rescue and betrayal collide.

In January 1945, Billy and Kaz arrive in Havana and immediately stumble into a double murder with Nazi intelligence in the background. To crack the case, they have to work with British operatives, Cuban underworld figures, and even Ian Fleming.