Before the dead ends and the false dawns, before the latest revenge killings and Secretary of State John Kerry’s quixotic shuttle diplomacy, there were people who believed that a lasting peace between Israelis and Palestinians was possible. One of them was a quiet American named Robert Ames, the subject of Kai Bird’s textured and absorbing book “The Good Spy.”

Ames was not only a spy but, as the title says, a good one. However, what exactly does that mean? He recruited few significant foreign agents to work for the C.I.A., falling short in what some inside the spy agency consider the true measure of a clandestine officer. The mission to which he devoted the bulk of his energies — maneuvering in the shadows to broker a Middle East peace deal — is, shall we say, unfinished.

Instead, as Bird artfully demonstrates, Ames was a good spy because he was a good listener, and “he listened with a plain sense of human empathy.” During the 1960s and ’70s, the Robert Ames Listening Tour played in Dhahran, Beirut, Sana, Tehran and other lesser cities throughout the Middle East. Ames died in 1983, along with 62 others, when a truck filled with explosives slammed into the American Embassy in Beirut.

Bird, the son of a Foreign Service officer who as a child was Ames’s neighbor in Dharan, has made a career writing impressively about American diplomatic history; he is also the co-author, with Martin J. Sherwin, of a Pulitzer Prize-winning biography of J. Robert Oppenheimer. But a biographer’s skills are tested when the material is thin, as seems to be the case with Ames’s early life in a working-class section of Philadelphia, which Bird sketches with generalities and clichés. The reader learns that Ames was a “steady, solid character” and a “serious young man.” On the basketball court he was “always a team player.” By the end of the first chapter, I feared I was embarking on an account of Beaver Cleaver’s adventures in Arabia.

But the book quickly becomes a rich, nuanced portrait of a man who, in the C.I.A.’s term, had “a high tolerance for ambiguity.” It is this trait that led Ames to develop a deep relationship — even a friendship — with Ali Hassan Salameh, the P.L.O.’s jet-setting, womanizing intelligence chief, whom the Israelis called “the Red Prince.” That relationship forms the narrative spine of much of the book, and Bird’s patient, detailed exposition of how the two men came to rely on each other is one of the best accounts we have of how espionage really works.

It was a thorny arrangement. Salameh had a role in terrorist attacks launched by Black September, the Palestinian group most famous for the 1972 massacre of Israeli athletes at the Munich Olympics; the Mossad believed Salameh himself was a chief planner of the operation. Bird says the evidence tying Salameh to Munich is murky, but Salameh was certainly involved in other Black September operations. “You sup with the Devil,” one spy put it, “but you use a long spoon.” Ames saw an opportunity for a back channel to Yasir Arafat, and hoped that the secret relationship might help nudge the P.L.O. toward a deal with the Israelis.

Salameh never went on the C.I.A.’s payroll, refusing to become an official “agent” for the spy service. Bird recounts how this led to grumbling inside the C.I.A. that Ames had difficulty closing the deal, but Ames knew that Salameh would consider it a betrayal to his cause to take money from Americans.

Yet this also left Salameh unprotected. When the Mossad asked the C.I.A. whether Salameh was an American agent, Langley faced a dilemma. If the answer was yes, the Mossad would have spared Salameh’s life. But the Israelis would also have demanded that the Americans share the intelligence Salameh was providing. The C.I.A. said nothing, and Salameh was killed in early 1979 in Beirut when a Mossad officer detonated a bomb hidden inside a Volkswagen.

Ames met his end four years later, an event that Bird recounts in heartbreaking detail. He sifts through the evidence in an attempt to determine who bore responsibility for the bombing, a case that for the most part remains unsolved, but ends on a curious note: Bird believes that a commander of Iran’s Revolutionary Guard, Ali Reza Asgari, played a central role in the bombing, and that Asgari may have later cut a deal with the C.I.A. to give up intelligence about Iran’s nuclear program. Bird says that Asgari is now living in the United States.

The C.I.A. has denied this assertion, but Bird has done a solid job investigating the episode. The puzzling part is that Bird clearly wants the reader to feel outrage that the C.I.A. may have brokered a deal with someone who had American blood on his hands — at the end of a book about a man who understood that such deals are part of the spying game. Nobody’s hands are clean — and nobody knew that better than Robert Ames.

Some months before Ames’s death, the C.I.A. had begun planning to escalate a secret operation in a different corner of the Muslim world, the effort to arm rebel fighters to battle Soviet troops in Afghanistan. What had originally been envisioned as low-grade harassment would grow to be the largest covert action of the Cold War, and contributed to thousands of Soviet military deaths. Not long after Jack Devine took over the C.I.A.’s Afghan Task Force, in early 1986, the Reagan administration decided to introduce a powerful new weapon into the conflict: American Stinger missiles capable of shooting down Soviet helicopter gunships.

In “Good Hunting,” Devine spins some fascinating yarns about his time running the covert Afghan war, from negotiating with the Pentagon for the Stingers to haggling over the price of AK-47s with Egyptian officials to buying mules from the Chinese. He also devotes considerable attention to his involvement in the story of Aldrich Ames, the C.I.A. officer turned Soviet spy with whom he crossed paths frequently throughout his career. The interactions between the two men over several decades illuminate how the C.I.A. has always been a small, closed society.

But the book suffers from the same problems that cripple so many spy memoirs. First, there’s the empty bragging. The chapter that recounts Devine’s ascent to a leadership job at Langley is titled “Raising the Bar,” and the book is marbled with phrases like “It’s fair to say I can put a tail on someone just about anywhere in the world faster than most spy agencies,” and “My job was to make decisions, and the consequences were always significant, so the pressure was high.”

Then there’s Devine’s depiction of nearly every C.I.A. officer he ever worked with as bright, resourceful and patriotic. In the author’s telling, the C.I.A. is Lake Wobegon, where everyone is above average and there’s scarcely a dolt in the entire organization.

Like many former spies, Devine is critical of intelligence reforms implemented after the 9/11 attacks, including the creation of a director of national intelligence — which Devine laments has “diminished” the C.I.A.’s role. That certainly was the concern at Langley when the position was created in 2005, but the opposite has occurred. The C.I.A. has only gained in power and influence, especially during the Obama administration. The spy agency is now in charge of America’s many secret wars abroad.

Just ask John Brennan, President Obama’s top White House counterterrorism adviser during the first term, who has had his pick of assignments in the second term. He’s now running the show at Langley.