Canadian actress-turned-director Sarah Polley landed Michelle Williams, Seth Rogen and Sarah Silverman for her first directorial outing since the Oscar-nominated “Away From Her.” Unfortunately, the mopey anti-romance she stuck them in didn’t take advantage of their full talents, and the wispy “Take This Waltz” barely earned a release.

With due cause.

It’s a conventional “meet cute” romance as Margot (Williams), who writes Canadian tourism brochures, stumbles into the flirtatious Daniel (Luke Kirby) at historic Louisbourg. They stumble into each other again on the flight home, and he’s pretty forward.

She, after a little hesitation, is intrigued — all the way through the shared cab ride from the airport home.

“I’m married.”

Oh. Daniel, it turns out, lives just across the street. He’s an artist who pulls a rickshaw for money. She’s married to a cookbook writer (a subdued Seth Rogen) who is all about different recipes for chicken. They have an adorable marriage of shared jokes, wonderful meals and parties that Lou (Rogen) caters to test out his latest culinary experiments on.

Something, however, is missing. How else do you explain Margot’s continued flirtation with the unscrupulous Daniel? She meets him for coffee, for a swim at the local pool. She wants to know “What you’d do to me” if she succumbs to his seduction. And he tells her, in graphic, not gushily romantic detail. She doesn’t exactly confess to her desire for a little passion to her filthy-mouthed alcoholic sister-in-law (Silverman). But in a shared shower at the gym, the idea of liking “something new” comes up. Older women sharing that shower advise her, “New things get old.”

Not that Margot listens. She keeps testing the waters — and swimming in them with Daniel, waiting for that moment to pull away.

Polley is famous for testing the boundaries of tone in her movies, keeping the viewer on his or her heels as the story and characters shift and manoeuvre and stake out this or that piece of ground.

Canadian actors flesh out the cast, songs by Canadian songwriters (Leonard Cohen’s title tune among them) score the melodrama. Lovely Canadian locations — the unfilmed corner of Toronto — grace the screen.

But “Take This Waltz” starts from a fairly unsavory premise with characters seemingly more curious than seriously motivated, and stumbles downward from there. It’s hard to find somebody to identify with — the bored (and boring) Margot, the perhaps-to-be-cuckolded Lou, the opportunistic Daniel?

Williams, de-glammed with a mousy haircut, plays as passive as her look here, letting (or not letting) things happen to her character, confused — tearing up at times, but never allowing us to invest in the character, whichever relationship she chooses to have. Rogen dials things down so far as to be bland, and Kirby is all smoldering looks and supposedly charming, persistent come-ons.

Silverman shines in her supporting role, willing to be nude and outrageous and unlikable in a movie where others are nude and just as unlikable, but not even remotely outrageous.

They’re just ordinary, flawed dreamers who can’t be told that “new things grow old” and have that advice take or mean anything.

MPAA Rating:R for language, some strong sexual content and graphic nudity

Cast: Michelle Williams, Luke Kirby, Seth Rogen, Sarah Silverman

Credits: Written and directed by Sarah Polley. A  Magnolia release.

Running time: 1:54