Over the course of several books set in Europe during World War II, Hadlyme novelist James R. Benn has created a much-loved and indelible character named Billy Boyle - a former Boston cop turned wartime staff investigator for his distant uncle, Dwight D. Eisenhower.

The stories are rich in evocative detail and Benn has proven ingenious at coming up not just with clever crimes and whodunnits, but also serving up all sorts of situations, locales and oft-forgotten minutiae about the war itself. Along with Boyle, an endearing support cast of recurring characters also has evolved, including the incredible Lieutenant Baron Piotr Augustus Kazimierz, aka "Kaz," Boyle's best friend - a fierce Polish anti-Nazi who serves as a translator for Eisenhower's staff and a sort of Watson to Boyle's Sherlock.

Earlier this week, the ninth Boyle mystery, "The Rest is Silence," came out from Benn's longtime publisher, Soho Crime, and Benn celebrates Saturday by kicking off a series of regional events with a signing from 5 to 7 p.m. today in Mystic's Bank Square Books.

In "The Rest is Silence," a decayed and anonymous corpse has washed up on the beach at Slapton Sands where Allied forces are engaged in Operation Tiger - intense and top secret rehearsals for the upcoming D-Day invasion - and Boyle and Kaz need to ID the body and figure out why he was in a tightly restricted area. Was he a German spy? A local criminal? A drunken sailor? They're assisted in this assignment by a local constable and former pilot, Tom Quick, and gradually determine his curious behavior is attributed to what would now be called post-traumatic stress syndrome after his wife and children were killed in a German bombing run.

Meanwhile, Boyle and Kaz are billeted in the modest nobleman's manor belonging to Kaz's old school pal, David Martindale, a former RAF fighter pilot who was horribly burned in battle. He shares the manor with several of his relatives including his wife, who is repelled by his scars; Sir Rupert, an ex-civil servant in India; Rupert's two grown daughters and their husbands; and an American-born possible heir to the estate no one knew about. Without meaning to, Boyle and Kaz are slowly drawn into a domestic conundrum that echoes the Brit-centric work of Agatha Christie.

Then, disaster hits, literally. Due to a communications faux pas during Operation Tiger live ammo exercises, more than 900 American soldiers are killed in friendly fire. Because of D-Day preparations, the incident is covered up and Boyle and Kaz are directed to discreetly investigate.

Yes, there are many plotlines, but Benn blends them beautifully and with a fine sense of tension and pacing. In addition to his usual page-devouring military mystery, then, he's added elements of a British tea-cozy and, even more impressively, engaged in a heartfelt study, through the characters of Quick and Martindale, of the emotional, mental and physical costs of war.

The book started with a simple idea.

"I definitely wanted to write about Slapton Sands, but it was a difficult idea because, given the secrecy required at the time, almost no one knows this happened," Benn said by phone last week. "It became a forgotten episode and I didn't know quite how to approach it. How would I get Billy involved? Would he be on one of the boats? Then the idea of the unknown body occurred to me. It was an a-ha! moment. Billy would have to investigate and that would be the entrée."

Benn says he also knew in advance that he wanted to explore David Martindale and write about the trauma and experiences of someone grotesquely disfigured while fighting for his country.

"I always remember a film from the 1960s called 'The Battle of Britain,'" Benn says. "It starred Michael Caine as this fighter pilot. And he walks into an RAF office with these burn scars and it was just indelible. I couldn't forget that image. He had this very British grace and I wanted to delve into that strength of character and courage a little more."

Tangentially, Quick - whose wounds and scars are mental - was going to have just a small role in the story.

"Tom was there just because I needed a local guy to help with the original investigation," Benn says. "I'd read a book that described the police in Britain who stood guard at the boundaries of the secured area, and that was the idea. But then he started to take on these wounded qualities that had a different context to what I'd ascribed to David Martindale. It was moving to write about their experiences."

Perhaps the most interesting part of "The Rest is Silence" are the activities within the manor house and the secretive, eccentric family of nobles. Stylistically, it seems a distinctly different twist for Boyle, but it flows well and Benn had a great time with it.

"It was a challenge, definitely," Benn says. "I deliberately made Ashcroft smaller and more modest and not too high society. I didn't want to go all 'Downton Abbey' and overwhelm the story. Sir Rupert's a working guy and that allowed me to focus on the family and the characters and how they fit in the overall story arc."

As always, Benn's conversational tones, period detail and depictions of the rhythms and cultural pace are spot on and, for certain readers, doubtlessly invoke nostalgia for a simpler, more genteel era.

"I do a lot of research and fact checking to make sure I get it right," Benn says. "And, doing so, I find that was a much more desirable world. Through my parents, I have a connection back even to the 1920s and '30s and I try to stay in touch with the things they handed down to me. Billy has that from his own father - there's a sort of time machine in our heads and sometimes it's good that we can turn back the clock a bit."

r.koster@theday.com

Twitter: @rickkoster

IF YOU GO

Who: James R. Benn

What: Book signing of "The Rest is Silence," the latest Billy Boyle World War II mystery

When: 5-7 p.m. today

Where: Bank Square Books, 53 West Main St., Mystic

For more information: (860) 536-3795

Other Upcoming Benn/Boyle events7:30 p.m. Monday - South Windsor Public Library, 1550 Sullivan Ave., South Windsor7 p.m. Oct. 17 - Lyme Public Library, 482 Hamburg Road, Lyme9 a.m.-6:30 p.m. Oct. 25 - CrimeCONN Mystery Conference, Westport Public Library, 20 Jesup Road, Westport