Gen. Dwight D. Eisenhower sees his wife, Mamie, after arriving home from World War II in this June 18, 1945, file photo from the Associated Press.

The First Wave, by James R. Benn

Dwight D. Eisenhower is best known as Gen. Eisenhower, leader of the Allied forces in Europe during World War II, or as President Eisenhower, leader of the free world at the height of the Cold War.

But to Lt. Billy Boyle, a young Irish cop from Boston, he’s “Uncle Ike.”

Boyle, the classic American reluctant hero in James R. Benn’s historical detective series, is a “second cousin twice removed on his mother’s side” to Kansas’ native son.

“The First Wave” (Soho Press, $24), the second novel in the series, is set in 1942 as Boyle lands on the shores of Algeria during the Allied invasion. His mission is to arrange for the surrender of the Vichy regime forces. In the meantime, Boyle also has to solve the murders linked to American black marketers who are working with the enemy to divert medical supplies.

World War II isn’t Boyle’s war, however.

“Billy, who is drafted into service, comes from a family with strong loyalties to the city of Boston and the Irish struggle against the British,” said Benn, 57, of Lyme, Conn. “They don’t really view this war as their war. They lost family members in the First World War, and as rabid IRA supporters they come up with a scheme to keep Billy safe.

“They pull some strings and get him assigned to an unknown general in Washington who is a distant relative. The general is Dwight D. Eisenhower.”

What the Boyles don’t know is Eisenhower is going to head up the entire Allied army in Europe. He takes Boyle with him as his secret investigator.

Benn got the idea for the Billy Boyle character while watching the first “Godfather” movie, which takes place during a family wedding in August 1945, right after the war.

“There is only one guy there in uniform, and that’s Michael Corleone,” Benn said. “He’s the white sheep in a family of black sheep. He joins the Marines and he’s at the wedding in his Marine uniform, highly decorated, and he’s the outsider. That’s what really struck me about the insular ethnic family, that to them, he was the sap. He went out and fought for the United States and the Corleone family was about their own family and their Mafia, and everything was about family.

“So I thought, ‘What if a guy from a family like that went off to war but didn’t want to? What kind of conflicts would that bring up?’ I just transferred that from the Mafia to cops.”

Benn’s series will follow the Allied campaign through Europe. He has just finished the draft of the third book, which is set in Sicily, where the U.S. Army is cooperating with the Mafia against fascists in Italy.

Expect Uncle Ike to play a key role.

“The response to Eisenhower from readers and the publisher was terrific,” Benn said of the first book, “Billy Boyle,” which was published last year. “They wanted to hear more from the general in future books. I had finished (‘The First Wave’) when all this happened, so I added a scene with him in it, making him more of an involved character.

“Also, I want to keep the series historically accurate. Always trying to keep the general’s appearances tied to actual events. So I won’t be fictionalizing his scenes as much.”