There are worse places to hide out than a cruise ship. Unless you’re the ship’s doctor. In “Wild Thing,” the Caribbean turns out to be less “Love Boat” and more “M*A*S*H” for Pietro Brnwa (a.k.a. Peter Brown). He’s the Mafia-hit-man-turned-surgeon introduced in Josh Bazell’s 2009 bestseller, “Beat the Reaper,” back now for a rousing, fast-paced sequel.

If the Costa Concordia accident hasn’t made you leery about booking a state room, Bazell’s description of the way the foreign staff members are exploited will. “Cruise ship doctors tend to burn out into either martyrs or Caligula,” Brnwa says.

Before his conscience totally crashes, Brnwa gets a new assignment from his witness-protection contact: A reclusive billionaire, dubbed Rec Bill, hires him to protect a paleontologist investigating rumors about a Minnesotan Loch Ness monster with a mouthful of vicious-looking teeth. Dr. Violet Hurst is a hard-drinking “bombshell” whom everyone keeps asking about a certain Steven Spielberg film. “The only part of the Jurassic Park movie Violet now considers realistic,” Brnwa notes, “is how everybody calls the male PhD ‘Dr. Grant’ and the female PhD Ellie.’ ”

Now a local entrepreneur is promising a $1 million adventure tour to prove the existence of the White Lake cryptid. Brnwa finds himself charged with protecting the paleontologist, but he’s skeptical that anything’s hiding in the water. He points out that 19th-century fur trappers would have made a felt hat out of anything unusual lurking near Lake Superior and says if Rec Bill wants “to see a rare living creature, go look at a polar bear.”

Still, because it’s hard to get a job as a doctor when you’re a former mob assassin in the witness-relocation program, he signs on to this watery venture despite his “shark issues.” (For the source of that phobia, see “Beat the Reaper,” which is being turned into an HBO series produced by Leonardo DiCaprio.)

”Wild Thing: A Novel” by Josh Bazell. (Reagan Arthur Books)

When Brnwa follows the gorgeous paleontologist to Ford, Minn., he discovers it isn’t exactly the kind of town that public radio celebrates. “Ford proper looks like someone’s used it to test-market the Apocalypse,” Brnwa observes. The women are strong (and often armed), the men aren’t much to look at and the children’s death rate is definitely above average. Last summer, two teenagers were killed in White Lake in what the local doctor called a “propeller accident.” But Hurst recognizes the bite marks from something that was thought extinct for 65 million years.

If the White Lake monster weren’t enough, there are local meth dealers, Mafia hit men and former governors to contend with. Bazell’s mix of violent lunacy and social commentary should appeal to fans of Carl Hiaasen, but Hiaasen avoids dating himself by keeping his politicians fictional. The monster hunt here is less goofy than the cameo from a prominent real-life Republican.

But the novel is packed with witty footnotes, and when Brnwa isn’t lusting after the paleontologist, he’s a profanely trenchant social observer. Although Brnwa never has to use his own fibula as a dagger as he did in “Beat the Reaper,” “Wild Thing” doesn’t so much end as explode. Bazell’s fans should have at least one more installment of inventive mayhem in store.

Zipp regularly reviews books for The Post and the Christian Science Monitor.

wild thing

By Josh Bazell

Reagan Arthur. 388 pp. $25.99