Chloe had its world premiere at the Toronto International Film Festival on Sunday night, less than six months after Natasha Richardson sustained a fatal head injury while skiing in Quebec.
Neeson, who is now making another film and did not attend the premiere, had departed the Toronto set of the film to be with his wife but returned the following week for his last few days of shooting.
After Richardson's death, "I got this e-mail from him that he wanted to come back and finish it right away, and that it was the best thing for him to do," Chloe director Atom Egoyan said in an interview on Monday.
"And that is just amazing. He's a consummate professional, and I think that's the smartest thing he could have done."
Chloe, inspired by the French drama Nathalie, revolves around a woman (Julianne Moore) who suspects her husband (Neeson) of cheating and hires a prostitute (Amanda Seyfried in the title role) to try to seduce him as proof of his infidelity.
The story twists into Fatal Attraction territory as lies, jealousy, suspicions and obsessions mount among the couple, their teenage son and Chloe.
"Everybody in this film has a somewhat different perception of the events and therefore a different reality," Moore said.
"It kind of explored a place in a marriage where they've been together for a long time and maybe felt they knew an awful lot about each other. And then one day, she goes, 'Oh my gosh, I don't think he's here at all."'
The key relationship in the film is between Moore and Seyfried's characters, with Neeson in a supporting role. Egoyan had directed Neeson in a play in New York City a year earlier and began pitching Chloe to the actor around that time.
"It was very generous of him to do this film, because it really is about the two women, and for an actor of that stature to do this role, it's a really generous thing," Egoyan said.
While the filmmakers were able to carry on with Chloe, Neeson's tragedy left a personal mark on his cast and crew mates, said producer Ivan Reitman.
"I think the biggest effect was the human impact, the realisation that life can change in an instant, and people we love or ourselves are here one moment, and then they're gone," Reitman said.
"It didn't change the film, but it changed all of us as human beings."
