It’s certainly ambitious, but “Cloud Atlas” comes thudding down to earth pretty quickly. The three-hour picture, an adaptation of the acclaimed but structurally complex novel by David Mitchell, shuffles together six separate story strands, ranging chronologically from the mid-nineteenth century to a twenty-fourth century post-apocalyptic future, into a thematically unified whole. But in the end watching it feels like eating a whole bowl of fortune cookies, all bearing the same message. You wind up feeling overstuffed and undernourished.

And what is the unifying theme of the film, made collaboratively by Lana and Andy Wachowski and Tom Tykwer? Not surprisingly it’s the same one propagated by the Wachowskis, in all their earlier pictures—the “Matrix” trilogy, “V for Vendetta” and even “Speed Racer”—the struggle for liberation from oppression. In the first segment, the issue is the abolition of African slaves; in the second, set in England in the 1930s, the ill-treatment of homosexuals and the control of artistic expression of innovators by the establishment; in the third, set in 1973, the danger posed by controlling capitalist corporations; in the fourth, a contemporary tale, the mistreatment of seniors housed in a brutal nursing home; in the fifth, in the Neo-Seoul of 2144, the struggle of a group of rebels against a totalitarian regime that utilizes genetic manipulation; and in the last, supposedly set in 2346, the fight of peasant farmers against a horde of brutal marauders.

There’s also a link connecting the various stories in a comet-shaped birthmark that we glimpse on characters in the various stories, a suggestion of reincarnation across the centuries. To add to that, more direct linkages are observable through the separate tales—a journal read by a character in a later thread, a story turned into a film that a character in a later one watches—as well as the fact that the actors play multiple roles across the six plot lines, often in makeup that renders them almost unrecognizable. The idea is obviously that the more things change, the more they stay the same—as in the repetitive refrain that “The weak are meat, and the strong do eat” that we hear—either directly or in our inner ear—throughout, indicating that the makers’ overall message is not exactly one of sweetness and light.

Which brings up another element that runs through the film—allusions to earlier ones. The 2144 sequence, starring Doona Bae as an engineered waitress who becomes the chosen spokesperson for the resistance, is essentially a retread of the whole “Matrix” mythology. It also contains obvious nods to “Blade Runner,” “Logan’s Run” and “Soylent Green,” and the latter title is even included in a line of dialogue elsewhere.

But apart from the modest fun movie buffs will have in catching these references, they don’t add much to the picture’s substance, which is basically just a reiteration of the same simple principle that freedom is good and control, in any form, evil. That’s certainly a fine point to make, but the Wachowskis have already made it repeatedly, and the treatment that they and Tykwer give it here just isn’t strong enough to achieve the profundity they’re striving for. And since the worst of the segments—those set in the future—tend to be the most spectacular (and spectacularly bad) ones, the effect is especially damaging.

Still, there are compensations. The most consistently entertaining of the six segments is the contemporary one, which plays like an old Ealing comedy with a nastier edge, and in which Jim Broadbent gives a superior turn as a wild-eyed publisher involuntarily committed to the home where the tyrannical Nurse Noakes (Hugh Weaving, in drag, in one of many of the “stretches” for the actors that doesn’t quite come off) presides. Broadbent also has a major role in the second-best section, the 1936 one (likewise directed by Tykwer) as the aging composer who takes a young gay gadabout (Ben Whishaw) as his amanuensis and then tries to steal his ideas.

Settling into the “mediocre” category of the film’s quality spectrum are the 1849 episode (the Wachowskis’ best), with Jim Sturgess as a young traveler who finds his true friend in an escaped slave (David Gyasi), though it’s disfigured by the very poor performance of Tom Hanks, encased in a rubber face so unconvincing it’s reminiscent of “The List of Adrian Messenger,” as a villainous doctor who tries to take advantage of him; and the 1973 segment, starring Halle Berry as an intrepid reporter who gets into deep trouble trying to uncover the corporate malfeasance of an energy mogul (Hugh Grant). It tries for a vibe similar to those of the great paranoid flicks of the 1970s, but Tykwer doesn’t manage to pull it off.

One reaches the doldrums with the Wachowskis’ two futuristic segments, the “Matrix” retread set in 2144 and the post-apocalyptic twenty-fourth century one featuring Hanks (again embarrassing, and speaking a horrible pidgin English he can barely deliver and we can hardly hear with giggling) as a meek goatherd who becomes a guide for a visitor (Berry again) from a technologically advanced society, perhaps not of this earth. Both of these suffer from the siblings’ characteristically juvenile approach, which was tolerable in the original “Matrix” because of its innovative visuals but has afflicted their work negatively ever since.

As to the cast, though you might respect their decision to take risks, those who impress most are the ones—like Broadbent, Whishaw and Sturgess—who stick closest to home, as it were. Hanks fares worst, with Grant not far behind, and Weaving’s succession of villains becomes a rather tiresome joke. Bae, Keith David, James D’Arcy, Gyasi and Susan Sarandon fall between the two extremes, neither awful nor exceptional. And technically the film is remarkable, given the scope. The production design by Uli Hanisch, art direction supervised by Stephen O. Gessier, Kai Koch and Charlie Revai, sets decorated by Rebecca Alleway and Peter Walpole and costumes by Kym Barrett and Pierre-Yves Gayraud are exceptional (though whoever is responsible for the “Mad Max” war-painted villains of the 2346 episode has some explaining to do). The cinematography by John Toll and Frank Griebe is equally praiseworthy, and the music by Tykwer, Johnny Klimek and Reinhold Heil certainly isn’t predictable—especially the “Cloud Atlas Sextet” featured in the 1936 segment.

It’s always nice to encounter a film with ideas to impart. It’s just a pity that those in “Cloud Atlas” are too small, and ineptly handled, to make this the epic rumination on human history its makers intended.