Sally Shelton-Colby needed to watch the documentary with friends, for emotional support. Seated in a Washington movie theater in October, she flipped open a notepad and, as the movie played, jotted down her thoughts. She filled out several pages.

The film concerned a dead man she’s still in love with. And the movie was made by someone she rarely ever speaks to. The film: “The Man Nobody Knew: In Search of My Father, CIA Spymaster William Colby.” Its director and narrator: his second-oldest son, Carl Colby.

Shelton-Colby, a former U.S. ambassador, was disturbed by her stepson’s take on her dead husband, and, as it turns out, so is the rest of the Washington-based Colby clan. They are especially upset with the film’s suggestion that the former spymaster spent his retirement in deep regret and killed himself on a canoeing trip in the mid-1990s.

For the Colby family, the movie is yet one more turbulent moment stemming from the career of their patriarch, whose CIA directorship in the 1970s is one of the agency’s most controversial. And even though Shelton-Colby, the spymaster’s second wife, has been kept at a distance by most of Colby’s biological children, their grievances with the film have united them, at least in principle.

“Let me be very blunt,” said Shelton-Colby, 67, a foreign policy professor at American University. “I think Carl portrayed his father in the way he did to sell his film. Carl didn’t know his father. . . . He was not the cold, insensitive, unfeeling person that Carl portrayed in that film.”

Carl Colby, whose documentary opened in September and is playing in theaters nationwide, declined to discuss his family’s reactions to his film. Although “The Man Nobody Knew” features an extensive interview with his biological mother, Barbara H. Colby, and more than 30 journalists, ex-CIA officials and other dignitaries, Carl did not ask his three siblings to be interviewed.

“I asked my mother, ‘What if [others in the family] all object?’ She said, ‘They can make their own movie,’ ” Carl said in an interview. “We all have our own relationships. The film is about the oldest question: Who are your father and mother? What do they mean to you?”

It’s been 15 years since Bill Colby vanished on a solo canoe trip near his vacation home in Southern Maryland, only to be found dead days later, floating on the banks of the Wicomico River. The CIA’s 10th director was best known for revealing the “family jewels” — a compilation of the agency’s assassination attempts, drug testing on unwitting humans and eavesdropping on war protesters. The disclosures in 1975, historians believe, saved the CIA from destruction when members of Congress were eager for its death, but they made Colby a pariah to CIA officers who believed such transparency imperiled the agency’s mission and national security.

Naturally, the CIA director’s death on a canoe ride triggered murder conspiracy theories. But now, “The Man Nobody Knew” has set off a tense division between Carl, his stepmother and his otherwise low-key siblings: Jonathan Colby, 65, a managing director at the Carlyle Group, an investment firm; Paul Colby, 56, a government attorney; and Christine Colby Giraudo, 51, a public relations consultant.

Only when contacted by a Post reporter did family members vent their frustrations about the film. Their dad’s legacy, they said, is something still worth defending.

In “The Man Nobody Knew,” Carl, the narrator, traces his father’s career as an intelligence operative in World War II to his tenure as CIA director. Carl paints his father as a mysterious family man more occupied with the agency’s mission against communism and less concerned about his wife Barbara and their five kids.

A divisive portrayal

In the film, Carl wonders whether his friends were right when they called his dad a “murderer” for running the notorious Phoenix Program — a CIA operation in the Vietnam War sought to ferret out Viet Cong agents in South Vietnam. Thousands of targets were killed, leading the media and much of America to call Phoenix an assassination program.

Even though the movie shows Bill testifying before Congress, saying that he issued an order against assassination, Paul, the youngest brother, said he still believes the film slams their father as a “mass assassin.” (In his memoir “Honorable Men,” Bill wrote that the vast majority of Phoenix deaths occurred “in combat actions” with Vietnamese and American military forces.)

Paul, who lives in Alexandria, also hates how the movie splices images of their dad with violent archival footage — rows of Vietnamese corpses and a notorious clip of a Vietnamese prisoner being shot in the head. Earlier this year, when Paul was shown the film, he told Carl that it would be “unethical” to keep it as is. Paul said the Vietnamese prisoner’s killing was not part of Phoenix, that his dad wasn’t even in Vietnam at the time of the shooting and that the footage is a “total smear of my father.”

“Carl told me that if I didn’t like it, I should make my own film,” Paul said. “The pain and sadness of losing [my father] has now been intensified by my brother Carl’s inexplicable and unfounded attempt to debase the reputation and memory of a modest and decent man, a dedicated father, and an exemplary public servant.”

Carl kept the wrenching footage to bolster the film’s credibility, he said. “The worst thing I could have done was to sugarcoat my father and paint things as rosy.”

Ultimately, the movie reveals Carl’s ambivalence about his dad. On the one hand, Carl comes off as bitter that his father was so immersed in his work. He feels his father left his wife isolated and eschewed real father-son bonds. On the other, Carl admired his dad’s public service and seems most proud of his disclosures to Congress about the CIA’s past misdeeds. “It’s a terrible thing to say, but sometimes I think I would have rather worked for him than be his son,” Carl said. “I would have been closer to him.”

The Colby family is bothered by the film’s suggestion that Bill killed himself because he felt guilty for not doing more to comfort his eldest daughter, Catherine Colby, before her death in 1973 from epilepsy and anorexia. Carl says in the movie that two weeks before the canoe trip his dad called him “seeking absolution for his not doing enough when Catherine was so ill.” When Bill’s body was found, his wallet contained a photo of Catherine, Carl says.

“Foul play was suspected, but I knew otherwise,” Carl narrates in the movie. “The coroner’s report listed the cause of death as a drowning, brought on by a stroke or heart attack. Call it whatever you like. I think he’d had enough of this life.”

In an interview, Jonathan Colby, who lives in Chevy Chase, said he does not understand why Carl implies that his dad committed suicide. “My dad’s shoes were off when they found his body, usually a sign of a drowning victim fighting to live,” he said.

Carl elaborated on his theory more in the interview, asserting that if his dad suffered a stroke or heart attack while canoeing, “he may not have had the will to live. When you are distraught, you do unreasonable, illogical things.”

Absent voices

Christine Colby Giraudo of Northwest Washington declined to be interviewed. In a short e-mail to The Post, she said her recollections of her dad differ from Carl’s. Through her sons, Barbara, 90, who lives in a Washington retirement community, also declined to be interviewed.

Carl said he didn’t interview his siblings because he views the film as his memoir, not a biography. His brothers and sister had their own relationship with him, he said. “It would have muddled the story.”

Carl said he felt that the best person to explain his dad was his mother, who was extensively interviewed in the film. But she does not share her son’s degree of bitterness. She admits to feeling jealous of another CIA wife whose husband talked more about his job. She also came to realize, after her husband asked her for a divorce, that she didn’t know him as well as she thought.

Carl seemed less intrigued by his dad after he left the CIA in 1976. “I preferred the old dad, not the new,” he said. “The old dad taught me how to sacrifice. The new dad . . . was just an ordinary guy with ordinary desires.”

Carl interviewed Shelton-Colby, but he opted not to use any of the footage. “She wasn’t forthcoming about any insights into his character,” Carl said. “The narrative ended. She’s just a coda.”

Life after the CIA

It was about 1982, Shelton-Colby recalled, and she met Bill Colby at the offices of International Business-Government Counsellors, a Washington consulting firm. Bill and Barbara were still married, but their relationship was deteriorating. Barbara had “no real voice” in their relationship anymore, Carl said.

Bill moved out of the family home in July 1983 to write a sequel to his memoir, Shelton-Colby said. Soon, she began courting him. Bill was initially reluctant, but he soon joined in the relationship.

The couple bonded over their backgrounds in foreign policy. And she, too, had been in a tired marriage — to a Mexican ambassador — that fell apart.

In 1984, Bill and Barbara divorced. That year, Bill and Shelton-Colby got married in Italy. On her nightstand by her bed, a photo shows the couple in Venice, seated in a gondola draped in flowers, yellow and white.

Over the next several years, they traveled the world. “Bill was working with newly Democratic elected parliaments in Eastern Europe to help them figure out how to assert authorities over spy agencies,” Shelton-Colby said. “He was having a ball.”

At their Georgetown home, after dinner, they had their rituals. They turned on the radio and danced the jitterbug or waltzed.

In April 1996, Bill set off on a worldwide consulting trip. He stopped in Mongolia to advise a mining company. The day after he returned, he went to his Southern Maryland home. Shelton-Colby was in Houston, visiting her ailing mother.

He drank some wine and ate some clams. Then he took the canoe out.

At Bill’s funeral the next month, Shelton-Colby, who wears on her left arm the watch she gave Bill as a wedding present, remembers one moment more than most. “It was when Barbara came up to me,” Shelton-Colby remembered. “And all she said to me was, ‘We both loved him.’ ”