Of the nine executive producers credited on “The Jacksons: A Family Dynasty,” four are Jacksons — Marlon, Jermaine, Tito and Jackie. From that much information, viewers will know better than to expect a blistering exposé. But then, it’s probably better to keep the dream, and the myths, alive anyway.

The six-hour reality miniseries, premiering Sunday night on the A&E channel, marks the first time that the family has opened its doors to filmmakers, and even if the family controlled the final result, there still are revealing and remarkable moments. None is more traumatic, of course, than the tragedy that brings Part 1 to a sobering close: June 25, 2009, when the Jacksons learned that their brightest star had fallen.

We in fact hear a recording of the 911 call placed when Michael was discovered unconscious, and see clips of the fan hordes who mourned in New York, Tokyo, Africa and London as news of his death circled the planet.

Michael’s passing devastated the family and also changed the nature and structure of the documentary, which was already well into the planning stages. Jermaine and the others decided to go on with the project, letting themselves be filmed as they grieved for their loss and the world’s. The film ends with the dedication, “In Loving Memory, Michael Joseph Jackson, Aug. 29, 1958 — June 25, 2009.”

Since we know what’s coming, the first 40 minutes or so of Part 1 also seem imbued with sorrow, partly because the brothers seem disheartened and a bit disoriented as they get together to plan a comeback — including a concert tour and a CD — celebrating their act’s 40th anniversary. Michael was to be a part of that. He still is, of course, but not as intended.

Unfortunately, much of the footage that precedes the heartbreak is humdrum and routine, capturing the brothers and other members of the real and extended family as they talk about themselves, visit one another’s lavish homes, sport around in a white Rolls-Royce, play backyard basketball (in scenes that seem like shameless padding) and take a sentimental journey to their home town of Gary, Ind. They, along with a song from Meredith Willson’s “The Music Man,” immortalized the once-industrial city, which looks sadly abandoned now.

Even so, a grand banner greets the brothers when they arrive: “Welcome Home, Jackson 5, Keepers of the Dream.” Earlier Jermaine had said nostalgically, “What’s real is Indiana — 2300 Jackson Street,” the address of their amazingly tiny childhood home.

Tears flow even before Michael’s demise. Jermaine confesses to his brothers and to the camera that he always felt “like an outsider” in the act and even more so during 10 years he spent on his own, accomplishing precious little. Divulging his hurt to the family, he breaks down weeping, followed by a major hugging session for all.

Although this part of the film is compelling, not much else really is, and you may get the feeling you are watching outtakes from a documentary rather than the real thing. Even more disheartening is a little recorded moment from an edition of “The Carol Burnett Show” in which Burnett introduces the Jackson 5, all decked out in powder blue. The scene brings back cheering and charming memories, which are, like the film clip, cruelly cut short. Even though the footage looks beautifully preserved or restored, we don’t get to hear a single Jackson 5 song, nor watch any of their heavy-on-charm choreography.

The filmmakers put too much value on intimate embarrassments and far too little on simple but satisfying entertainment, which would have helped with the hour’s pacing and range. It’s all several shades too somber, and it seems awfully churlish of the producers to tease us with mere glimpses of the Jackson 5 when a few complete numbers — even just one — would have been most welcome relief.

Janet Jackson literally phones in her contribution, unseen as she calls on her birthday; no one says which one. Then the brothers go back to rehearsing wearily in a recording studio, failing to spark or to recapture what one of them calls “that old Jackson 5 magic.” Tito tells his brothers, “You guys sound like the Supremes,” which is true even when they talk.

The remaining five hours will follow the Jacksons as they try to get their act, or as close to it as possible, together. It may be interesting to watch them struggle, but it’s not likely to be fascinating, especially when the man at the center of it all is not there. “His spirit is very much alive,” Jermaine says of Michael, but that turns out to be more of a problem for “The Jacksons” than a blessing.

The Jacksons: A Family Dynasty

(one hour) premieres Sunday night with back-to-back episodes on A&E at 9.