Hollywood has built an entire genre out of the idea of government conspiracy, the shadowy intelligence figures who are not what they seem, out of control and well out of reach. With current levels of distrust reaching post-Watergate levels, a spate of new projects may not so much reflect the times as fan the flames.

The documentary “The Man Nobody Knew,” rolling out in limited release, challenges presumptions in polarizing times.

It is a very personal examination of one of the 20th century’s most accomplished yet opaque spymasters, William Colby, who built a career on keeping secrets, but ended it by sharing many of them.

Told by his son, filmmaker Carl Colby, it describes his father’s ghost-like presence in the family home as he devoted himself to WWII and later to Cold War espionage out of a sense of duty and a dose of derring-do, including masterful covert operations and savvy counterinsurgency missions. But his career ran aground just as he reached his peak as CIA director in the Nixon and Ford administrations. With revelations that the CIA was involved in domestic spying and assassination attempts, Congress launched hearings in 1975, putting his father in the spotlight.

Rather than obfuscate, Colby’s testimony, much to the dismay of the Ford administration, revealed many of the agency’s darkest secrets. Not until he took over the agency was he made aware of most of the so-called “family jewels.”

Through it all, Colby never seemed to flinch. Seymour Hersh, who broke the story of the CIA’s overreach, recounts interviewing Colby. “He didn’t lie to me,” Hersh says. “If I said there were at least 120 cases of wiretapping of American citizens, contrary to the law in America, he says, ‘My number is only 63.’ It was a question of numbers. He did not back away from the question of wrongdoing.”

As Carl says, his father was “a very complex person — but also simple in his construction.” His favorite film characters were Lawrence of Arabia and Harry Lime, the amoral opportunist from “The Third Man.” When Colby asked his dad about the latter, he gave a wan smile and kind of shrugged. “That is who he dealt with. He dealt with the Harry Limes of the world, not the Joseph Cottens of the world,” Carl says.

Perhaps his father’s most controversial assignment was his overseeing the Phoenix Program, part of an American pacification effort in Vietnam. Designed to neutralize Viet Cong opposition at the village level, including the use of targeted assassination, it proved , successful, yet pushed moral bounds.

Then in his teens, Carl says he began to have doubts about his father whom he “adored” as a boy. He began to ask questions like, “What is he doing? Why is he not coming home? Why does he look past me?” Colby pushed for a full-scale evacuation and rescue of allies as Saigon fell in 1975, but was rebuffed by Secretary of State Henry Kissinger. It was soon after that Colby was called before the congressional hearings. Former National Security adviser Brent Scowcroft talked of Colby as a “tortured soul” during that time, and wonders whether he was “expatiating his sins,” but Carl says that his father was amazingly calm as he’d turn on the evening news and watch himself under fire by an array of elected officials. “The American public will be fed up with it at a certain point,” he told his son at the time. “These senators will understand.” Carl says he saw his father was the sacrificial lamb, and he was right. The revelations saved the agency but not Colby’s career. Shortly after, he was replaced by George H.W. Bush.

Carl’s movie has flashes of reverence and atonement, but mainly leaves his father just as the title suggests, an enigma. That’s similar to where it leaves the whole idea of well-intentioned, covert operations in the name of patriotism but fraught with moral doubt, something that will come through in Clint Eastwood’s upcoming “J. Edgar.” George Clooney’s “Ides of March,” an adaptation of hit play “Farragut North,” deals in campaign corruption, secrets and lies in a drive for political power.

The irony is that, for all the mistrust in government, it’s currently aimed at Congress, not as much at the intelligence agencies.

As Carl says, in light of the killing of Osama bin Laden and an emphasis on special forces and drone strikes, the CIA has been given a “blank check,” and President Obama is cashing it.

Whereas his father was a “tainted warrior” forced to go before congressional hearings, Carl says it’s unlikely a senator would dare question current CIA director Gen. David Petraeus.

“He has more respect than they do,” Carl says, adding, “I have nothing against covert action. It has its place. But don’t get too enamored of it, because when it goes wrong, there’s hell to pay, and it will probably be the agency that has to pay it.”