‘Chloe’ creates an odd triangle on and off-screen

They make for a very unlikely trio of collaborators: Ivan Reitman, director and producer of blockbuster Hollywood comedies, art house director Atom Egoyan and Erin Cressida Wilson, writer of the cult hit “Secretary.” Yet, they have come together as producer, director and writer, respectively, on the dark, sexy thriller “Chloe,” which opens Friday.

Perhaps even more unusual than the collaboration itself is the genesis of the partnership: It started with “Ghostbusters” director Reitman, who first saw the French erotic thriller “Nathalie . . . ,” directed by Anne Fontaine, at the 2003 Toronto International Film Festival and became interested in pursuing a remake. He sought out Wilson to collaborate on the screenplay with the initial intention to direct the film himself.

The film tells the story of Catherine and David Stewart (Julianne Moore and Liam Neeson), a successful Toronto couple -- she’s an OB-GYN, he’s a music professor -- who have grown distant over their long marriage.

Concerned that her husband might be cheating, Catherine hires a call girl, Chloe (Amanda Seyfried), to see if he can be seduced. Implicitly understanding that the wife wants more than knowledge of unfaithfulness, Chloe begins to tell Catherine intimate details of liaisons with David. When Catherine attempts to pull back from the arrangement, Chloe pursues her son, entangling them all in a web of jealousy and obsession that will have irreparable consequences.

“I’ve been married a long time, and I think sexuality in marriage, particularly long-term marriages, is an interesting subject that we almost barely touch in Hollywood,” Reitman said. “And I was looking for an interesting movie to direct that was really different than anything I had done previously in my career. So, I thought, ‘Let’s see where this can go.’ ”

But as the project progressed over a number of years, Reitman realized he might not be the best director for the job. He turned to Egoyan, director of “Exotica” and the powerful drama “The Sweet Hereafter,” to take on the project.

“It was really just a sense of, ‘Yes, I could do this movie, but this guy’s going to do a better job than me,’ ” Reitman said. “It’s so much more in his wheelhouse than mine, and as tempted as I was to try something like that, I guess my instincts as a producer sort of took over, and I felt like the actors and what they’d have to do for the film would be more comfortable with him directing than me directing.”

The film maps the icy remove of Egoyan’s sensibility onto the structure of an overheated erotic thriller. By playing it straight-faced, “Chloe” manages to be insightful and alluring while also unafraid to be slightly ridiculous -- imagine a 1990s Michael Douglas thriller with Julianne Moore cast as Michael Douglas.

“If all she wanted was information, she could have hired a detective,” Egoyan said of the deeper motivations behind the actions of Moore’s character. “She’s not sure what she wants, but once she begins to hear it, there is something both lurid and exciting but weirdly punishing as well.”

“I thought it was a fun challenge to bring a character study to a piece of pop entertainment,” Wilson added. “The film is about paranoia that builds between four different people, but my hope is it’s actually fun and salacious and sexy and scary as much as it is thoughtful and deep and occasionally funny.

“My joke is I was Chloe when I started and I ended up as Catherine by the time I was done.”

Wilson’s original screenplay was set in San Francisco, but when Egoyan came aboard, it was transposed to Toronto.

Shooting Toronto as Toronto, being able to show off some of the city’s notable contemporary architecture in ways that can’t be done when the city so frequently acts as a stand-in for other locations, was particularly intriguing for Egoyan.

“In a way,” Egoyan said, “given what the film is about, at the level of metaphor it’s interesting because Toronto is a prostitute, as a city very often it pretends to be New York or Chicago or San Francisco. So it’s interesting that since this is a film about that, that in fact the city becomes a character.”

In a flip of the typical tropes of the erotic thriller, “Chloe” focuses on a woman coming to grips with her own diminishing sense of being desired, something of a female anxiety variation on male virility issues, providing a rarely glimpsed window onto marriage, aging and sexuality.

Though it would be facile to do so, the film could even be read as somehow pro-adultery, or at least as suggesting that sometimes long-term relationships need something to jolt them from their everyday complacency.

“I think of it as pro-communication, pro-fantasy and pro-intimacy,” countered Wilson. “No matter what age we are, we still have desires, and marriages aren’t just still things. They are growing organisms that change, and they go through these terrible times sometimes and we get through them or sometimes we don’t. And people do the darndest things.”

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