John Sandford just keeps barreling along. ESCAPE CLAUSE, his latest Virgil Flowers offering, contains some of his best writing, no small feat for a guy who is within hailing distance of completing his third decade as a novelist. Virgil Flowers, who walks a fine line between adherence to duty and insubordination in each installment of this outstanding series, manages with a bit of maneuvering to see that justice is appropriately done on a couple of different fronts without putting his position in jeopardy.

ESCAPE CLAUSE utilizes a plot device that is no stranger to Sandford’s novels --- that in which all (or at least a great deal) is revealed to the reader while the protagonist, Virgil and the Minnesota Bureau of Criminal Apprehension (BCA), is left to play catch up. The book opens with the brazen theft of a pair of two very rare and valuable Amur tigers from the Minnesota Zoo. The crime is discovered rather quickly; given the public outrage over the abduction, the pressure is on Virgil and the BCA to recover the tigers while they’re still alive. Virgil and his team are able to uncover an important clue rather quickly, due to nothing more or less than solid and steady police work, but following the path to the tigers is still slow going.

"As with the best of novels, ESCAPE CLAUSE takes the reader into new and different areas of knowledge. Sandford goes deeply into the world of alternative medicine, particularly that subgenre that illegally utilizes animal parts, and the result is horrific."

The person behind the thefts is Winston Peck VI, an M.D. whose license to practice has been revoked but who considers himself an expert in alternative forms of medicine. Peck is a bad guy, but he attempts to become even worse during the course of the book, and succeeds. His reason is nothing more or less than greed, given that there is a very lucrative market in alternative Asian medicine for drugs made from the body parts of a tiger, particularly Amur tigers. That market, however, is also extremely illegal, a fact that does not deter Peck, his somewhat hapless colleagues, or his potential buyer. While Peck’s primary nemesis is Virgil, his worst enemy is himself and the giant monkey he is carrying around on his back in the form of a Xanax addiction, which is so far out of control that he is barely able to function on a sustained basis. But even with that, Peck has an animal instinct and cunning --- a good degree of believable luck --- that keeps him operating, at least for a while.

Meanwhile, Virgil has a secondary case that he is pursuing somewhat unofficially. Frankie, Virgil’s lady-in-waiting, has a sister called (not named) Sparkle, who appears on the scene with the aim of investigating a local food processing plant that uses illegal immigrants in harsh working conditions. Sparkle’s investigation puts those around her in danger, including her own sister. Virgil finds a way to even up the odds as the two cases unexpectedly and briefly converge in a believable and satisfactory manner.

As with the best of novels, ESCAPE CLAUSE takes the reader into new and different areas of knowledge. Sandford goes deeply into the world of alternative medicine, particularly that subgenre that illegally utilizes animal parts, and the result is horrific. You don’t have to be a member of PETA to be horrified by what is revealed. There is also a vignette that demonstrates how one can lose a pursuer while being followed (I was going to describe that as “losing a tail,” but it might have caused confusion), a method that you wouldn’t have been able to utilize even five years ago. It’s worth the price of admission all by itself.

If there is a weakness, it is that some of ESCAPE CLAUSE is formulaic. More than likely, you will see the story’s climax coming by the time you have completed the first fourth of the book. Still, you won’t be disappointed when it comes to pass. Getting to that point constitutes a good deal of the entertainment and, yes, absolute joy of a Sandford novel, as it does in this case watching the irony unfold back on the bad guys, in different and fitting ways. Oh, and the title of this worthy thriller? It’s my favorite of this (and maybe any) year.