It’s not all that clear what “Married Life” thinks of married life. Is the strain of matrimony a burden too great to bear, or an obstacle well worth clearing, provided you’ve found the right companion? Whatever the final analysis, “Married Life” is at least certain about one thing: Marriage is an institution established by and primarily for men. Women are just along for the ride.

A hybridized thriller-soap opera that seems to be suffering from an advanced case of multiple personality disorder, Ira Sachs’s new film can’t quite find its bearings, much less keep its balance long enough to walk a viewer through the turbulent ups and downs of marital vows, cohabitation, and lifelong commitment. Ultimately, “Married Life,” which was written by Mr. Sachs and “I’m Not There” co-scribe Oren Moverman, loses its sizzle as it tries to balance B-movie fun and Oscar-minded doses of social commentary.

That said, the film is liveliest when at its most sordid. Harry (a methodical and oh-so-tame Chris Cooper), a supposed embodiment of dignified postwar America, sits down one sunny afternoon with his close friend, Richard Langley (a conniving Pierce Brosnan), in November 1949. In a matter-of-fact fashion, with the look of a man lifting a weight from his chest, Harry informs Richard of the news: He’s going to leave his wife Pat (Patricia Clarkson) for a younger woman. A few minutes later, in strolls Kay (an effervescent Rachel McAdams), a ravishing beauty who seemingly holds the hearts of both men in her hands.

“Married Life” would almost be better told as three separate stories — “The Adulterer,” “The Murderer,” and “The Seducer.” In one of the three threads, we see how Harry, so stoic and chiseled in public, devolves into a state of giddiness when he visits Kay’s home. She elicits something in him that, whether real or perceived, no one else does — especially Pat, who has become less a romantic interest in Harry’s life than a roommate.

But when Harry finally tries to tell Pat that he doesn’t love her anymore, she suffers a panic attack. Harry calls the doctor and commits himself to never again causing her such anguish. Instead, he decides to try to kill her. But if Harry is both the adulterer and the would-be murderer, then Richard is the seducer, the man who cajoles his best friend’s mistress into discarding her married lover. When Kay obliges, Harry suddenly finds himself in danger of losing all the love he has known.

There’s something about “Married Life,” which made its premiere at last year’s New York Film Festival, that takes a while to sink in. With hindsight, the marital maze seems far more compelling, and a bit spicier, than it did in the theater. Taken as a whole, and viewed through a cynic’s eyes, it’s really a scathing character study. Pat, it seems, is not all that different from Harry, aware that their fire has been extinguished, and that their initial passion has been replaced by something unfamiliar and cold. For his part, Harry is not all that different from Richard, wanting that which he cannot possess. And really, Kay and Pat both want the same thing, namely stability and affection, in no particular order.

But as arranged on the screen, something about these poignant — and at times painful — profiles becomes diluted by a series of double crosses that don’t pack the emotional punch Mr. Sachs seems to think they do. Harry’s murder plot is interrupted so frequently that it’s hard to fully appreciate his sharp turn to the dark side. Richard’s rushed courting of Kay seems unlikely, mostly because we’re shut out of the scenes in which she evidently caves in to his charms. It also doesn’t help that the film’s notion of marital angst in the 1950s is a subject that’s already been explored recently, notably on the television series “Mad Men,” which in many ways was more electric than “Married Life.”

Perhaps the problems can be traced to Messrs. Sachs and Overman’s adaptation of the John Bingham novel, as well as to the disastrously underwritten character of Kay, who appears far too rarely and says far too little to convince us that she has stolen Harry’s heart or fallen for Richard. If we’re not buying her character, then we can’t buy much else that happens in this fractured love story.

It’s the women in “Married Life” — both the brushed-aside wife and the taken-for-granted adulteress — who need more attention here, not only from their men but also from their creators.

ssnyder@nysun.com