There has been a lot of talk about HBO losing touch with its audience in the post-“Sopranos” era, and one does wonder who exactly will be sitting down to watch its latest show, “Tell Me You Love Me,” a sexually graphic, microscopically detailed depiction of troubled relationships that makes its premiere on Sunday.

One can only imagine the dread with which uncommunicative, distraught, or plain fed up couples will regard the arrival of this 10-episode series on the television schedule. Happier pairs, or freewheeling singles, may tune in because they’re curious about the sex, but they may tune out again once they realize that erotic naturalism has its limits, and that there won’t be any threesomes, lesbian time-outs, wives dressing up as policewomen, or even a mild slap on the fanny.

The show examines three couples. Katie and Dave (Ally Walker and Tim DeKay) are a painfully decent, caring, 40-something pair with two kids and a sex life that has gone from oatmeal-bland to nonexistent. Carolyn and Palek (Sonya Walger and Adam Scott) are slightly chillier, Don DeLillo-ish professionals in their 30s (she’s a lawyer, he’s an architect). They have plenty of sex, but Carolyn’s obsession with getting pregnant— which seems neurotic since she doesn’t particularly like children—and Palek’s ambivalent feelings about fatherhood slowly destroy the sex and then everything else. Jamie (Michelle Borth) is a 27-year-old, amorous hottie prone to unreasonable jealousy, which causes endless problems (including her own retributive infidelities) in her relationship with Hugo (Luke Farrell Kirby), a schoolteacher who loves her but can’t convince her that he’ll be faithful to her until they both drop dead.

The only real link between the couples, aside from coincidental encounters, is that they all visit May Foster (Jane Alexander), a couples therapist in her 60s with a mane of white hair and a happy marriage to Arthur (David Selby). The Fosters continue to enjoy an active sex life and, no, we are not spared their wintry, surprisingly vigorous lovemaking.

“Tell Me You Love Me” — a slightly inappropriate title, since the main characters are constantly saying, “I love you” — becomes increasingly engrossing as it goes along. It creates real suspense around which couples are going to break up or stay together (and why), the therapy sessions are as squirm-inducing as any masochist could wish for, and the question of whether the vast iceberg at the center of Katie and Dave’s double bed will ever melt slowly builds to thrillerish proportions.

The fear going in is that “Tell Me” will be some sort of prolonged advertisement for couples therapy. On balance, the therapy does come out favorably, but hits enough authentically rough patches to make you wonder if anyone in the audience who hasn’t already done so would even consider submitting to its rigors. The film is also unafraid to expose the hideousness of much therapy-speak. “I think you’re examining some very valid issues,” May says at one point. Or, “Tell me about you. Tell me where you’ve been.”

The sex for which the show has garnered so much attention is as realistically presented as advertised, but it turns out to be the least interesting thing about the series over the long haul. While it’s true, as Nancy Franklin pointed out in the New Yorker, that “Tell Me” breaks new ground by keeping the cameras rolling (in the bedroom) long after most programs have politely closed the door, it sometimes loses the sensuality for the sexuality, cutting away too soon from other scenes.

One example comes late in the series when poor, repressed, love-starved Katie, who sports plain suburban leisure wear and only a dash of makeup, is set upon by an eager sales assistant in the makeup section of a department store. The scene in which she shyly sits back as the young black woman starts to apply blush and eyeliner and all the rest of it, all with the most expert of gossamer touches, is by this point far sexier, or sensual, or moving, than yet another session between the couples, whose naked grapplings are reproduced to the point of boredom. But the camera cuts away before Katie even gets to try on some new lipstick. Given that the series was created by a woman, Cynthia Mort, this struck me as surprising.

The characters’ material circumstances are all thoroughly comfortable. They live in big airy houses (or in the case of the younger couple, a roomy apartment), and no one has gone bald or developed three chins along with a bad case of eczema. (During one therapy session, Katie claims to have reached an age at which she doesn’t even recognize her body anymore — to which most people would say: Doesn’t look bad to me, babe.”) There are no illnesses or crises that, in many parts of the world, including this one, would be counted as serious or worthy of attention. Yet these people are members of a class for whom the weight of expectation surrounding sexuality and personal fulfillment has reached crushing levels — and that can be almost as cruel a taskmaster as poverty.

This is something the show’s writers seem keenly aware of. At the same time, they realize that’s the way our society works. These privileged couples don’t live in a world where there are so many more immediately pressing problems than the quality of your orgasm or whether your husband really wants a child, that you don’t have time to think about it all that much. Like it or not, they live in upper-middle-class America, where the god of personal fulfillment is indeed a fearsome, imperious god.

Aside from four-time Oscar nominee Jane Alexander (also a former head of the National Endowment for the Arts), the actors on “Tell Me” range from the not-very-famous to the fairly obscure. Hollywood may be very much in favor of sexual freedom, but there’s only so much skin its stars are willing to show, and few are willing to be caught masturbating on-screen. On the whole, the low-profile cast works for the series, adding to its naturalism. Mr. Scott is particularly good as the rootless architect, Palek, and Ms. Walker is deeply affecting as Katie.

One can quibble about certain aspects of the series, particularly its almost complete humorlessness, but on reflection it’s hard to see where the funny parts would fit. “It’s better to be quarreling than lonesome,” goes an Irish proverb in favor of couples staying together. But it doesn’t mention anything about jokes.

bbernhard@nysun.com