John Sandford is on to something. The Minnesota author of 25 crime-suspense novels has just published "Heat Lightning," his second featuring Minnesota detective Virgil Flowers.

Like all Sandford books, its cop-shop realism, high-wire action and authentic dialogue pull the reader along to a satisfying climax. But what makes the Virgil Flowers books so fascinating is the way Sandford crafts them: He has help.

In his acknowledgments, Sandford notes that he wrote "Heat Lighting" "in cooperation with my old friend and hunting partner Chuck Logan -- the author of a bunch of thrillers of his own -- the latest being 'South of Shiloh' from HarperCollins."

Sandford is the pen name of former St. Paul Pioneer Press reporter (and Pulitzer Prize winner) John Camp. Logan is a former graphic artist for that newspaper who launched his own writing career and has penned eight crime novels.

Sandford's first Virgil Flowers book, "Dark of the Moon," was written last year in collaboration with Larry Millett, a former architecture critic for the Pioneer Press who has written a half-dozen successful Sherlock Holmes books. Reviews indicate that "Dark" has the complexity of a typical Holmes whodunit, with the gritty characters that Sandford fans have come to love.

Logan filled me in on how this latest collaboration worked. "I think he's just having fun doing it," he said. "It's fun working with John, and I had this yarn I thought we could play with. It's kind of a spinoff of an old idea I had. I thought, what the heck?"

So Logan forged the plot and Sandford polished the prose.

"Essentially, I did the research and set up the machinery for the story," Logan said. "I wrote what I call uninflected narrative so that John could take it and put it in his own voice."

Logan spent about eight months on the project, and his framework shows through Sandford's impressive characterization and dialogue.

The story takes place over a hot, sticky Minnesota summer. Virgil Flowers, a hard-drinking but gifted detective, is in bed with his second ex-wife when his boss, Lucas Davenport, calls about a bizarre murder in Stillwater. A man's body had been found at the veterans' memorial with two shots to the head and a lemon stuffed in the mouth. The grisly scene resembles a previous killing in New Ulm, down to the .22-caliber weapon used and the signature lemon -- an unpublished detail that ruled out a copycat killing.

Ghosts of the Vietnam War often animate Logan's stories. And in "Heat Lightning," he finds a way to keep the war a central theme. Sandford keeps the book timely by setting the killings just before the Republican National Convention in St. Paul. Minnesota readers will appreciate the physical and cultural landmarks that serve as the book's canvas.

Heat lightning is a meteorological term that signifies a storm brewing on the horizon. It implies we'll see more of Virgil Flowers. And it makes me wonder whether Sandford has more collaborations brewing with his other former colleagues at the Pioneer Press who've gone on to write crime thrillers, Theresa Monsour and Rick Shefchik. Regardless, I'm looking forward to the next installment. Meantime, I'm going to pick up a copy of "Dark of the Moon" to see what I missed.

Dan Browning is an editor at the Star Tribune.