In this stunning autobiography “Priceless: How I Went Undercover to Rescue the World’s Stolen Treasures” (Crown, $25), former FBI undercover agent Robert K. Wittman details his 20-year career investigating the murky world of art theft.

Adopting the false but carefully documented identity of Bob Clay, a shady art dealer with a taste for contraband, Wittman successfully infiltrated domestic and international criminal networks to recover more than $225 million worth of stolen cultural property — items ranging from a Rembrandt self-portrait to an original copy of the U.S. Bill of Rights.

Wittman also came closer than anyone else in the world to unraveling the mysterious 1990 robbery at Boston’s Isabella Stewart Gardner Museum. His encounters with criminals closely associated with the theft make for some of the most riveting chapters in the book, providing new and surprising information about the heist and the probable whereabouts of the Gardner’s missing Rembrandt and Vermeer.

Authoritative and superbly crafted, “Priceless” is absolutely, hands down, the best book ever written on art crime. It is also a fascinating memoir, giving readers a look at the real-life challenges of a career in law enforcement: Wittman’s day might begin with him donning a bulletproof vest to take part in a sting operation and end with him joining his wife to pump out their basement, flooded by a brutal Northeast storm.

A self-effacing patriot, Wittman says he initially joined the FBI “because it seemed like honorable work and a good way to serve the country.” He encountered his share of frustration dealing with Washington bureaucrats, about whom he writes with wry humor, but he never let office politics or poor pay distract him from his steadfast pursuit of the world’s misappropriated cultural treasures.

“Money is here today and gone tomorrow,” Wittman says. “These objects are our history.”