Cloak and founders.

Washington's Spies: The Story of America's First Spy Ring, by Alexander Rose (Bantam, 384 pp., $26)

THE History Channel recently gave us Washington the Warrior; thanks to Alexander Rose, we now have Washington the Spymaster. This fascinating and carefully crafted book shows us a side of the Father of Our Country that hero-worshipers since Reverend Weems never imagined--and the almost forgotten covert side of the Revolutionary War. We see George Washington advising his agents about invisible ink and encryption pads; brushing letters with a chemical wash to expose secret messages; wondering whether one of his spies might be a double agent; and trying to arrange an exchange of captured spies with the British, as if in a scene from a Hollywood espionage thriller.

Is it so surprising? Alex Rose reminds us that Washington started his military career in secret ops, working as the equivalent of an intelligence officer during the French and Indian War. As supreme commander in the American Revolution, he understood that--in the words of his subordinate Nathaniel Greene--"intelligence is the life of everything in war." (Millennia earlier, Sun Tzu was even blunter: "All warfare is deception.")

Indeed, Washington's first act as commander of the Continental Army was to launch a disinformation campaign. Upon appointment by the Continental Congress, he had been assured that there were 300 barrels of gunpowder waiting for him in Boston. When he arrived in July 1775, he learned that there were only 30--barely enough for one round per soldier. So Washington put it about that he was actually sitting on 1,800 barrels--enough to fight a major war. He knew Loyalist spies in Boston would carry the story back to British headquarters, which they did. The deception convinced General Howe to hold off on attacking Washington's outnumbered troops; and in March 1776, the British army evacuated Boston without firing a shot.

That summer, the theater of war was shifting from Boston to New York City, and Washington desperately needed information about British plans. The espionage duel began in earnest. Washington's first agent was to become the most famous, Nathan Hale. But as Rose points out, Hale was probably also the most ineffectual. He never entered into the spirit of the thing; unlike Washington, he couldn't convince himself that espionage was a proper calling for a gentleman. Even his handlers thought Hale too open and honest to make a good spy.

And so the British scooped Hale up almost before he got started, and left him dangling from a tree in what is now Manhattan's East Side--at 3rd Avenue and 66th Street. Nathan Hale's last words (which Rose concludes he never uttered)--"I regret that I have but one life to give for my country"--put him in the pantheon of American revolutionary martyrs. But as an intelligence agent, Hale would have been laughed out of the Aruba Secret Service.

His successors proved a better fit for the business of cloak and dagger. Their story is the heart of Rose's book, and he gives us a compelling portrait of this rogues' gallery of barkeeps, misfits, hypochondriacs, part-time smugglers, and full-time neurotics that will remind every reader of the cast of a John le Carre novel.

Running the show was the taciturn Benjamin Tallmadge, who had been Nathan Hale's classmate at Yale and a captain of dragoons--the era's equivalent of mounted scouts. At first Washington had Tallmadge gather intelligence on British troop movements; but then he set him to work organizing an elaborate network of spies in New York City and across rural Long Island, the famous "Culper Ring." As Washington's "M," Tallmadge recruited the colonial era's James Bonds, men like Abraham Woodhull (a.k.a. "Samuel Culper"), Austin Roe, and Robert Townsend. They were men who lived mainly on the margins of respectable society; men whose eccentric religious beliefs or shady business dealings had already made deceit a daily habit, but who were also committed to the revolutionary cause (although the money Washington paid them didn't hurt, either).

Tallmadge wove these disparate characters into an effective espionage operation, complete with encoded cyphers, invisible ink (Washington introduced Tallmadge to that subterfuge), and counterintelligence operations against similar Tory spy rings. The risks of being caught were great. General Howe hanged three New York women on suspicion of being spies; American soldiers would string up a man for having a guilty face ("a faithful index of the heart," claimed Gen. Alexander McDougall). All but one of the Culper Ring were bachelors. None were well-to-do; one or two ended up bankrupt after the war. One suspects they felt they had little to lose.

Other interesting rascals pass through Rose's racy narrative, notably William Heron, codename "Hiram," the classic double agent who regularly sold information from his American handler to his British handler, and vice versa; Robert Rogers, organizer of Rogers's Rangers, who was Nathan Hale's captor and interrogator; and British major John Andre and Benedict Arnold, who together nearly pulled off the espionage coup of the century until they ran afoul of Benjamin Tallmadge.

It was Tallmadge who connected some suspicious maps of West Point--which Andre had in his possession when he was caught--with Benedict Arnold. If Tallmadge's advice to arrest Arnold immediately had been followed, the general turned traitor would have joined Andre on the hangman's tree, instead of escaping to die sick and destitute in exile in London. For Washington, Benedict Arnold was--in intelligence terms--The Big One That Got Away. Arnold knew the names of many of Washington's spies operating behind British lines. Washington desperately tried to arrange an exchange of Andre for Arnold, without success. He even talked to Nathaniel Greene about trying to kidnap Arnold from the British--a "covert operation" worthy of Allen Dulles and E. Howard Hunt.

Fortunately, the Continental Congress didn't subpoena Greene or Tallmadge, to demand, "What did the general know, and when did he know it?" Today, of course, the hanging of Major Andre would be considered a war crime worthy of impeachment. And Benedict Arnold would be the author of a bestselling memoir detailing how he tried to blow the whistle on George Washington's attempts to undermine our civil liberties--with Alec Baldwin playing him in the movie.

Mr. Herman is the author, most recently, of To Rule the Waves: How the British Navy Shaped the Modern World(Harper Collins/Perennial).