I remember a year or so ago when Justin Trudeau was asked a snarky question about quantum computing, and proceeded to explain it in language we could understand…and the whole concept of things being two things at once kind of blew my mind. “Things can be in two places at once. The coin is both heads and tails. The cat is alive and dead. A bit is zero and one. It’s only the act of observing these phenomena that collapses their ambiguous state. ” In The Quantum Spy, the race is on between the U.S. and China to build the first quantum computer.

It’s a great setup for David Ignatius of the Washington Post to entertain us with a 21st century spy thriller…and, thanks to W.W. Norton and NetGalley, I received a copy in exchange for this honest review.

Early on, we meet John Vandel, long-time CIA operative, who is wise to what it takes to survive in the Agency: “He wrote an eyes-only memo later that morning for the national security adviser to cover himself. The rest, he didn’t want to know. The Director was a former member of Congress. Letting the staff do the dirty work was a way of life.”

Some years ago, an Army Ranger named Harris Chang saved Vandel’s life in Iraq. When Vandel thanked him, Chang said “You would have done it for me,” to which Vandel replied “No fucking way.” This tells us quite a bit about both men, and as the story alternates locations including China, Singapore, Washington, D.C., Iraq and Seattle, we follow their efforts to beat China in the race for quantum computing superiority.

Chang goes to a quantum research lab that has been compromised by a suspected Chinese informant. There is a hunt for the mole who may have penetrated the highest levels of the Agency, and things hop around, with a bit of uncertainty that parallels the quantum state: there are leaks, but do the leaks expose real secrets, or are they false trails meant to deceive the Chinese? Chang finds that there is a thin line between loyalty and betrayal, as he follows the path of the investigation wherever it leads.

Sometimes techno-thrillers can be daunting, with details that are beyond the casual reader of spy novels. In this one, Ignatius has done a great job of combining a twisting plot with self-revelation that parallels the paradox of quantum computing. Chang is the model of a conflicted spy who has dealt with racism and bigotry his entire life, and who faces his own duality as he works to solve the puzzle surrounding the mole.

Spy novel fans, computer buffs, mystery lovers, and anyone who likes a plot with lots of twists and well-developed characters will love this one. Five stars.