In the opening frames of Ira Sachs' witty, suspenseful and deliciously lazy comedy/murder mystery, two middle-aged businessmen – best friends, prosperous past the point of smugness – spend a long, languid and expensive lunch hour discussing the pitfalls of marriage, especially exiting one in midstream. One of the men, Rich Langley (Pierce Brosnan), a confirmed bachelor back before the word took on suspicious connotations, listens with incredulity as his old buddy, Harry Allen (Chris Cooper), announces he's walking out on his wife Pat for a much younger woman.

"For Pat love means only one thing."

"What is that?"

The scene abruptly shifts to the Allen's living room where a cheeky Pat (a new career peak for an elegantly sensual Patricia Clarkson) finishes Harry's sentence.

"Sex – all the rest of it, the romantic dreams, the self-deception, what you always call 'the wish to give and give,' Harry – it all boils down to bed. Love is sex! The rest is affection and companionship."

"You're completely and utterly wrong."

"You're a romantic and sentimental fool. If you don't want the truth, you shouldn't ask me questions. (Pause) But I do love you, darling, really."

In his first film, The Delta, Memphis-raised Ira Sachs allowed us to spy on a world of anonymous sex between men in a modern Southern city, a world that turns quite unexpectedly murderous; his next, Forty Shades of Blue , deliciously explored the break up of a complicated marriage between a powerful music mogul and an emotionally precarious, much younger woman; his latest, Married Life, is a less experimental but equally provocative take on why a once comfortable relationship can without warning implode into homicide.

For the meticulous Sachs, whose early films radiated the persistent decadence of a city that's always too close to the boiling point to ever be thought safely civilized, Married Life is a continental shift to the old money precincts of John Cheever country.

Sachs turns Brosnan's seemingly reliable narrator into a suave rake, with his own agenda – a man who shifts the spotlight from his own failings with a droll account of his old pal Harry's fall from grace, including a just short of slapstick plan to poison Pat. It's 1949 right before the country's post-World War II euphoria curdles into Cold War paranoia. It's a flush time when many Americans feel no need to ration their appetites or their dreams, a time for putting the top down on the convertible, for going to the movies, for smoking at the movies, for smoking and drinking 24/7 – a sexy goodnight line has a suitor asking a date to hand him her cigarette, in lieu of nightcap, "because it's touched your lips."

When Rich takes Harry up on his invitation to visit Harry's girl, Kay – Rachel McAdams is perky and sweet as a restless war widow, who's given herself a blonde makeover, complete with a sizzling hot brand of rosy red lipstick – we sense that dancing check to check will prompt another matrimonial double cross.

Sachs delicately juggles a mystery with a social comedy where everybody's competing for a scarlet letter. Chris Cooper excels as nebbish who in channeling his dark side remains charmingly na�ve about the motives of those closest to him.

Spoiler alert: an unlikely victim will pay for the sins of a feckless quintet whose misdeeds oscillate between Hitchcock and Woody Allen.

Director/writer (with Oren Moverman) Ira Sachs confesses a huge debt to the films of Joan Crawford and 40's pulpy novels:

Ira Sachs: I discovered Joan Crawford late and I was struck by how her films seem both totally over-the-top and completely nonsensical and yet completely honest about relationships and the way people are in life. I think the metaphor of some of those movies – whether Harriet Craig or Sudden Fear – really spoke to me. This is a mystery film about the human heart.

I spent a summer reading pulp fiction and found this book, actually very well written, called Five Roundabouts to Heaven by John Bingham, a mystery writer who was also a member of the (British intelligence service) MI5. He was John Le Carre's mentor – the man upon whom the character of Smiley was based. I think (a) spy is not unlike a married man. For me married life is a state of being, not an institution – any long term relationship, gay or straight, in which there's intimacy over time.

Lamble: Your film reminds me of John Cheever.

Sachs: As a teenager I (saw) The Swimmer, the Burt Lancaster film based on Cheever. Cheever has a lot of empathy for his characters, a real softness, also a gay quality in his approach to character and a kind of feminine nature.

There's an upper crust nature to the characters – they're not driven by money at this point in their lives. I grew up in Memphis in an upper middle class Jewish community. There was a sort of elegance to that time and to my grandparents that I tried to (invoke in) the film.

Lamble: Your next film has a gay setting.

Sachs: It's The Goodbye People, (from) two novels by Gavin Lambert. Gavin was a screenwriter/novelist, who was gay and British, living in LA in the '50s and '60s. It's set in the late '60s, with a multiplicity of sexual behavior.