Modern thrillers are gritty

"It's my pleasure to meet the Kroger people in person, share a Mexican meal and learn about their business," she said. "They are going to promote my new FBI thriller ... at all of their stores, and that's a wonderful thing."

Flash drives and cloud computing are as crucial in contemporary thrillers as are AK-47s and C4. And writers are tasked as never earlier to get their facts in order, says Grant, whose novels feature British spy David Trevellyan. A third Trevellyan novel is in the works.

"There are new kinds of weapons and new ways of deploying them," he says. "We all perceive this unconventional enemy now, this amorphous enemy. And an unconventional enemy calls for an unconventional hero."

The genteel thrillers of old

And some readers might miss the genteel thrillers of old, many of which featured more dialogue, more quiet reflection by thoughtful protagonists and fewer explosions. "In a le Carré novel," says Morrell, co-founder of a group called International Thriller Writers, "his guys just sit around and talk. Le Carré had as a matter of fact been in the spy business, and he introduced a lot of the terms we now take for granted — mole, double agent. However there's no action."