Setting Sights ‘To Kill the Leopard’ : Theodore Taylor of Laguna Beach says the maritime WW II saga he has long wanted to write is his best adult effort.

He’s best known as an award-winning author of young adult novels, but over the past seven years Theodore Taylor of Laguna Beach has carved out a successful career as writer of adult thrillers.

His latest, “To Kill the Leopard” (Harcourt Brace; $21.95), is described by Publishers Weekly as a “high-impact techno-thriller.” Set in the North Atlantic and France during World War II, the novel pits American merchant marine officer Sully Jordan against German submarine captain Horst Kammerer in a gripping, vividly realistic maritime war saga.

“It’s the best adult book I’ve ever done,” says Taylor. “I have good feelings for it.”

So, apparently, does his publisher, which is taking out full-page ads in the book review sections of both the Los Angeles Times and New York Times--a first for Taylor.

Last week, Harcourt Brace also flew Taylor to the American Booksellers Assn. convention in Miami where he did a signing and spoke at a Sunday breakfast for booksellers.

Taylor, himself a war veteran of 18 months in the merchant marine in the North Atlantic, Mediterranean, Caribbean and Gulf of Mexico, spent three weeks on a research trip to France, where he visited the still-existing German submarine pens at Lorient.

“This book is something I’ve had in mind for years and years, and I finally got around to doing it,” Taylor said by phone from Miami. “I researched extensively to do the German part, and I had help: a French admiral who helped on Lorient and a former member of the German navy who lives in Orange County, Manfred Krutein. I don’t speak German and I don’t read German, so he translated the technical stuff for me.”

Although the great land battles of World War II and the sea battles of Midway, Coral Sea and the Philippines received the headlines, Taylor said the most desperate and vicious warfare was waged practically unsung in the Atlantic.

“It was the most deadly part of the war and proportionately more merchant mariners were lost than in any other service,” he said, noting that more than 63,000 Allied merchant sailors and armed guard personnel were killed. “It’s one of those things I kept thinking to myself: No one has really done this story. So I finally did it.”

Taylor said he enjoys alternating between writing adult and young adult novels.

“It’s just a nice change of pace,” he said. “The book I have in the typewriter right now is an adult thriller.”

But there’s good news for Taylor’s young adult fans: “Timothy of the Cay,” the prequel to his award-wining 1969 young adult novel “The Cay,” will be published by Harcourt Brace in September. (“The Cay” has sold 2.5 million copies worldwide in hardback and paperback.)