Is there anything more painful to watch than a flat, shapeless farce? Certainly it’s no fun sitting through an arch, clumsy effort like “Merci Docteur Rey,” while flails away like a wounded beast before collapsing in narrative disarray. The sense of desperation is palpable, not only on the screen but increasingly among the audience, who are likely to feel trapped and queasy by the halfway point. Medical intervention may be necessary.

The linchpin of the intricate but messy script is Thomas Beaumont (handsome but bland Stanislas Merhar), a young gay Parisian trying to connect with a kindred spirit through male-seeking-male classifieds. Thomas’ mother purportedly widowed Elizabeth (Dianne Wiest, totally miscast and never remotely convincing) is an operatic diva starring in a new production of “Turandot” staged by her flamboyant friend Claude (Bulle Ogier). Somehow–in what is but the most unlikely of the coincidences scattered throughout the story–Thomas gets “invited” by one of his ad contacts to hide in an apartment closet and watch an older man named Bob (Simon Callow, in what amounts to an unsavory cameo)–who just turns out to be the father he’d long thought dead!–be murdered by his young lover (inexpressive Karim Saleh). Thomas then impulsively decides to visit the titular psychiatrist, only to arrive in her office just after the doctor has dropped dead during a session with a long-time patient, Penelope (manic Jane Birkin), a near-hysteric actress ho specializes in dubbing all of Vanessa Redgrave’s film performances into French. For some reason Penelope pretends to be Dr. Rey when Thomas shows up and begins offering him advice; and though the imposture is quickly revealed, they go off together anyway, leaving the corpse behind. Meanwhile Elizabeth comes to believe–again, for reasons that are never clarified–that Thomas has been abducted, but that plot thread is soon abandoned in favor of one involving a police investigation of Bob’s death, with suspicion inevitably falling on Thomas. To add to the unlikeliness, Elizabeth and Thomas both get involved individually with the murderer, and at one point even Redgrave, playing herself, shows up for a sour in-joke involving Penelope. Alice B. Toklas-style marijuana-laced brownies also make an appearance, to no particular effect. The ending is very peculiar–a feel-good group hug that entirely ignores the deaths that led up to it.

There’s a muddled, frantic air about “Merci Docteur Rey” that’s especially dispiriting when combined with Andrew Litvack’s halting, uncertain direction. If his script was to have any chance of working, it would need a light, carefree approach, but here everything is played in a stentorian, heavy-handed fashion that smothers any glimmer of wit or style. So the picture is not only poorly written but ineptly staged, and the performers either underplay so dully (like Merhar) or mug so ferociously (like Birkin) that the movie never achieves any sense of balance of comic consistency. A few nice shots of outdoor Paris apart, the picture is visually pedestrian–which is perhaps appropriate, since the characters walk the streets a lot.

Astoundingly, “Merci Docteur Rey” is a Merchant Ivory production (Litvack was a crew member on some of their films, and their support is apparently an act of friendship, but one untouched by good sense). The only reasonable reaction to a misbegotten bit of curdled whimsy like this one is to exclaim: Mercy!