That John Lennon contained multitudes and mysteries was clear to anyone who listened to him when he was in the Beatles and after he discovered himself anew with Yoko Ono, who united with him mind, body and soul. They first met in 1966, kept in touch and finally shared a long night that ended with their making love at dawn. “It was very beautiful,” Lennon later said. They were still together in 1980 when he was fatally shot in New York City. He was only 40. In the years since his death, Ono — who turned 92 in February and has retreated from public view — has helped keep him vividly present through her art, music and activism.

Lennon and sometimes Ono are exhilaratingly present in “One to One: John & Yoko,” a documentary flooded with music and feeling that revisits a narrow if eventful period in the couple’s life. Directed by Kevin Macdonald and heroically edited by Sam Rice-Edwards (who’s also the co-director), the movie focuses on the early 1970s when Lennon and Ono were living in a modest apartment in the West Village amid clutter, clouds of smoke (cigarette and otherwise) and a hardworking television. “I just like TV,” an off-screen Lennon says in the documentary. “Whatever it is,” he adds, “that’s the image of ourselves that we’re portraying.”

The image of Lennon and Ono in “One to One” is of an appealing, loving, creatively — and politically — fired-up couple who have happily lost and found themselves in the ferment of New York. By the time they landed in the city in 1971, Lennon and Ono were married, and the Beatles were no more. (The group made it legal in 1974.) When the couple met in 1966 it had been at one of her gallery shows. There, Lennon climbed a ladder featured in one of Ono’s artworks to read a single word that she had scribbled on the ceiling: “Yes.” Perhaps it was prophetic: They were married to other people, but soon said yes to each other, leading to a lot of ugliness directed at Ono, who was wrongly blamed for the Beatles’ breakup.

For “One to One,” Macdonald has drawn from a wealth of engrossing, at times arresting archival material, including footage of Lennon and Ono at home, as well as never-before-released phone calls, for a movie that is as busy and as populated as their lives appeared to be. Allen Ginsberg pops up here, once while reciting best practices for anal hygiene. So do Angela Davis, Phil Spector, George Wallace and Jerry Rubin, who spoke about revolution alongside Lennon and Ono on “The Mike Douglas Show” in an eye-popping 1972 clip. Cinephile alert! The blond guest in that snippet is filmmaker Barbara Loden, whose “Wanda” opened the year before. Lennon was right: TV was worth watching then.

In making the documentary, Macdonald et al. have taken an immersive rather than an instructional approach, one that plunges viewers into a rushing stream of moving and still images, among them home movies, concert footage, news reports and far too many period commercials. There are no original voice-overs or talking-head interviews to help guide the way, and most of the text on-screen is transcripts of the phone calls. There are, less happily and helpfully, far too many shots of a re-creation of their apartment made specifically for the movie. (Ono and Lennon’s son, Sean Ono Lennon, served as the music producer.)

The thread that winds throughout “One to One” is the Aug. 30, 1972, concert of the movie’s title that Lennon and Ono coordinated at Madison Square Garden alongside the likes of Stevie Wonder and Roberta Flack. Earlier that year, television reporter Geraldo Rivera had shocked the viewing public with a harrowing expose of the Willowbrook State School on Staten Island, an institution for people with developmental disabilities where the children’s ward was crowded with grimly neglected boys and girls. Horrified, Lennon and Ono helped organize the event (they performed twice that day) to raise money for the children; it was, as the movie puts it, “the only full-length concert John gave after leaving the Beatles.”

The nonconcert footage is meant to bridge the personal and the political, and to convey the banalities and horrors of the early 1970s as well as to illuminate Lennon and Ono’s activism. To that end, the filmmakers gesture at the national divide, one that seems starkly familiar when they cut to a blazingly red electoral map that illustrates Richard Nixon’s landslide presidential victory. At other times, as the movie skitters from more ads to politicians and Vietnam War casualties, whatever the filmmakers hoped to say about the Lennon, Ono, America, consumerism, the society of the spectacle and so on, gets lost in a blur that becomes so much visual wallpaper. That may be the point, but the dead in this movie deserve more sensitivity.

The lack of specifics in “One to One” can be frustrating, particularly for those who are more familiar with Lennon and Ono’s history. Viewers who’ve read and watched other work about him may wonder if the clicks that he mentions hearing on his phone could be from the FBI, which had put him under surveillance in 1971 for his anti-war activities. Other fans will recognize the name May Pang, an assistant of the couple who, starting in 1973, had an affair with Lennon that’s discreetly elided here. Admirers of Ono’s work may also wonder why the documentary includes so many, often humorous phone calls in which Lennon-Ono associates talk about wrangling houseflies for an uncompleted art project.

However funny the fly talk (among other things, these folks were hunting flies for rock stars), it has a whiff of the same condescending attitude that Ono’s conceptual art sometimes drew. That’s too bad. You see glimpses of her work (including her 1970 film “Fly”), but I wish the movie had fewer TV ads and more on her as a serious artist. In the years since Lennon’s death, her profile has continued to rise to the point that my New York Times colleague Lindsay Zoladz recently wondered if we are living through, as she phrased it, a Yokossance. Here’s hoping. You may not really know much more about Lennon and Ono at the end of this movie than at its start, but you do learn that it must have been cool to hang with them. But, oh, more Yoko please!