Fast cars, hot guys, murders, mysteries and a 140-pound Saint Bernard named Beans: They all combine to make “Motor Mouth” an action-packed page-turner.

Janet Evanovich delivers another racy mystery with “Motor Mouth” (Harper-Collins, $26.95), the sequel to “Metro Girl,” part of her new series set in the world of NASCAR.

Both racing fans and those who don’t know a pit crew from a Pitt Stop gas station will be captivated by “Motor Mouth” from the green flag to the finish line.

Barney is a bleach-blond bombshell who serves as Sam Hooker’s racing spotter.

Hooker is a hunky race car driver who cleverly tries to seduce Barney as they work on solving a twisted murder mystery – the death of a prominent racing team owner. Along the way, they manage to become suspects and have to fight to clear their names.

If the stolen cars, dead bodies and detailed descriptions of Miami don’t hold your attention, the scenes when ultra-feminine Barney kicks bad-guy butt will.

“Horse turned toward me, and I roundhoused him in the face with the six-pack of soda. There was a satisfying crunch, and blood spurted out of Horse’s nose. … I ran to the front of the lot screaming, ‘Fire! Fire!”‘

The novel takes on a typical good vs. evil theme and succeeds in blurring the distinction between the two, forcing the reader to consider what “good” really means.

The story follows Barney and Hooker from Miami’s South Beach to Concord, N.C.

When the NASCAR season is over, Barney heads home to a place that resembles the live-work community at the Village at Sandhill: “If Disneyland had been built by the Gap, it would look like my Huntersville neighborhood. It’s a contrived town with stores and restaurants at the ground level and apartments above.”

Evanovich writes with humor and edge. She takes an ordinary “what if” situation and creates an absurd reality for her characters. But her use of local color and description keeps the reader grounded and engaged.

She weaves NASCAR terminology and details into the story naturally, so it’s not overbearing or boring to readers unfamiliar with racing: “I’m Sam Hooker’s race-day spotter. I’m the lip-glossed, bleached blonde who whispers into Hooker’s ear while he sweats his brains out in a black-and-gold fire-resistant jumpsuit each week.”

“Motor Mouth” revs with action and intensity. Buckle your seatbelt before turning the pages of Barney’s misadventures.