You know a picture is in serious trouble when it begins with a huge swath of narration and then periodically returns to extensive voiceovers throughout its running-time. The practice indicates that the filmmaker hasn’t any idea how to dramatize his material in a truly cinematic way, and so resorts to telling us verbally what he’s supposed to be showing us through a mixture of intelligent dialogue, editing, and acting. The narration in “The Invisible Circus,” which Adam Brooks has adapted from a novel by Jennifer Egan, seems endless; in the first reel of the picture, it’s practically non-stop, bluntly informing us of all the characters’ histories, motives and ambitions, and thereafter it recurs regularly to explain flashbacks, let us in on what people are thinking or feeling, and basically tell us how we’re supposed to react to the plot. The desperation seems evident in every scene, and it makes the picture, despite its relatively brevity, feel interminable.

“Circus” is a nostalgia-laden coming-of-age story set up as a road movie with a supposedly profound political and personal mystery at its core. But in the final analysis it isn’t much more than a soap opera, and a bad soap opera at that. Set in 1977 but including scads of flashbacks to the late sixties and early seventies, the scenario focuses on eighteen-year old Phoebe (Jordana Brewster), a spunky California girl who goes to Europe to retrace the steps of her beloved older sister Faith (Cameron Diaz), who committed suicide in Portugal six years before. Driven to discover why Faith, an idealistic hippie type, should have ended her own life, Phoebe hooks up in Paris with Wolf (Christopher Eccleston), Faith’s old boyfriend, who’s reluctant to discuss the circumstances of her death but eventually proves a font of information while also getting romantically involved with the younger sibling. The solution involves Faith’s unhappy involvement with the radical groups that were so prevalent in various European locales during the decade of revolution, and by coming to terms with the truth Phoebe finds herself and can get on with her own life (the final line of dialogue is a numbingly banal expression of her self-realization). But the denouement brings no great, satisfying revelations, and the only truly mysterious thing remains why such a limp, obvious tale was ever thought worthy of transformation into a motion picture in the first place.

A good deal of the emphasis in “The Invisible Circus” is on the recreation of period detail, and every frame shows how intently this was pursued on a very limited budget. The scenes set on a San Francisco street at the beginning and end are shot in such a way that strategically-situated 1970s autos are prominently displayed; and a good deal of attention is given to the properly absurd-looking clothes of the period. But while the visual has been given much thought, the general mood and atmosphere of the time are much less successfully caught. Every gesture and inflection seems perversely wrong, from the ludicrous depiction of hippie California parties to the crudely inserted allusions to contemporary events (montages of predictable stock footage are occasionally employed, against which the newly-shot scenes seem utterly fraudulent). And the performances certainly don’t help. Brewster, an erstwhile daytime TV ingenue, is pathetically stiff as Phoebe–she does an especially awful under-the-influence sequence at one point in the flick, and her romantic encounters with Eccleston’s Wolf are staged with laughable pretentiousness. Eccleston himself is a talented actor, but his material here is pedestrian at best, and he looks positively embarrassing with extra-long hair in the flashback scenes. Diaz flounces about gamely as the driven Faith (whose faith is ultimately destroyed by events, get it?), but she’s never remotely convincing in the role’s permutation from wide-eyed free spirit to disillusioned would-be terrorist. Blythe Danner and Patrick Bergin barely reach TV-movie standards as the girls’ parents.

To be fair, one can occasionally take one’s mind off the deficiencies of the script and execution by simply concentrating on the European locations, a few of which are nicely rendered by cinematographer Henry Braham. But otherwise there’s painfully little that’s enlightening, provocative or engaging in this third-rate “Circus.” One line of dialogue is especially memorable, however, in summing up the experience of watching it. At one point during her stay in Amsterdam, a drug-addled Phoebe is accosted by an apparition of Faith in a store window, which the ghostlike figure encourages her to break so the two sisters can be together again. Phoebe tries, but banging against the glass proves painful (as well as unsuccessful). “You’ve got to be willing to suffer a little,” the wraith points out. Sitting through “The Invisible Circus,” on the other hand, means being willing to suffer a lot.