When Americans think about the CIA today — if they think about it at all — they probably picture a secluded compound in Langley, Va., where Matt Damon matches wits with Joan Allen.

But those who grew up in the 1960s and 1970s conjure a very different image: an agency shrouded in rumors of LSD experiments, foreign assassination plots and booby-trapped cigars — all of which seemed thoroughly outlandish until proven true by the relentless investigators of the Senate Intelligence Committee and Seymour Hersh of the New York Times.

Jefferson Morley is of that generation, and he has brought the investigative tools of a veteran journalist to that murky era — specifically, to the career of James Jesus Angleton, the CIA’s legendary chain-smoking, orchid-growing, poetry-quoting chief of counterintelligence.

The result is “The Ghost,’’ a page-turning biography of an eccentric spy hunter. But it’s also a carefully documented argument that the CIA, an agency created to defend the ideals of democracy from fascism and communism, wound up tarnishing those ideals instead.

Morley grew up in Minneapolis (his father was a respected editorial writer for the Star Tribune), attended Yale (itself a CIA recruiting ground for years) and spent 15 years at the Washington Post, where he sharpened his interest in national security.

In Angleton, he has a character beyond the imagination of John LeCarré, perhaps even of Patricia Highsmith.

The son of a wealthy expatriate American businessman, Angleton grew up in Milan, studied English at Yale, published an influential literary magazine before he turned 20, and befriended the brilliant but bigoted poet Ezra Pound. Then, obsessed with fascism and foreign affairs, he talked his way into a job with U.S. Army intelligence as World War II broke out.

Angleton was, as they say, in the right place at the right time. He met and charmed Allen Dulles, soon to be the first civilian director of the CIA. For training, he was dispatched to Bletchley Park, the British espionage headquarters, where he apprenticed with legendary British spies such as Kim Philby.

Readers who recognize Philby’s name will understand that Angleton was entering treacherous territory. And it got treacherous fast. Sent to Italy at the war’s conclusion, Angleton befriended a group of fascist henchmen — war criminals, almost certainly — and protected them from prosecution because he thought they would be valuable allies in the looming Cold War.

Back in Washington in the early 1950s, he helped oversee the CIA program known as MKUltra, which experimented with hallucinogens and hypnosis to brainwash foreign agents. When an Army scientist named Frank Olson exited Manhattan’s Statler Hotel via a 10th-floor window and a shower of broken glass while tripping on LSD, Angleton discovered that covering up the CIA’s secrets mattered as much as exposing those of the Soviets.

Morley makes a gripping yarn of this material, but he also weaves a deeply tragic weft. While no one doubts Angleton’s brilliance and patriotism, Morley demonstrates that his obsession with communism and Soviet moles clouded his professional judgment and his moral compass.

In what may be the book’s bombshell, Morley details Angleton’s early surveillance of Lee Harvey Oswald, but shows that his paranoia led him to misread Oswald’s motives and, almost certainly, obstruct justice in his dealings with the Warren Commission.

In September 1975, Angleton was called before the Senate Intelligence Committee in an appearance that would make headlines around the world. Under blistering questions from Sens. Frank Church and Walter Mondale, the broken spymaster could not deny, or even defend, CIA tactics that violated its charter and federal law. Instead, he prevaricated:

“It is inconceivable,’’ he insisted, “that a secret intelligence arm of the government has to comply with all the overt orders of government.’’

The words marked the end of his career and the end of an era, and they may explain why the audience always cheers for Matt Damon.

 Dave Hage is an editor at the Star Tribune.

The Ghost
By: Jefferson Morley.
Publisher: St. Martin's Press, 336 pages, $27.99.
Event: 7 p.m. Nov. 10, Magers & Quinn Booksellers, 3038 Hennepin Av. S., Mpls.