In "Secret Love Affair," Kim Hee Ae's character at first resists the advances of the love-struck genius piano prodigy played by Yoo Ah In. But once she gives in, her character Oh Hye Won becomes a reckless woman in love.

Kim Hee Ae gives a steamy and convincing performance as a woman who risks losing her marriage and career for a man who is 20 years younger.

"She's perfect for the role; she's prudent and reserved, resulting in a more unconventional effect when she exposes her sexy, revealing side," said co-star Yoo Ah In.

It's not the first time Kim Hee Ae played a seductive woman in an adulterous affair and the last time she did so, her acting was so convincing it generated break-up rumors about her real-life marriage.

When Kim Hee Ae played the seducer of a married man in the 2007 drama "My Man's Woman," her portrayal was so convincing that rumors said she was about to break up with her real life husband Lee Chan Jin. Rumors even circulated that the couple was already separated, which came as a complete surprise to them.

The rumors not only shocked the actress and her husband but everyone who knew her. Her fellow actors on the set said she was a devoted wife who called her husband a few times a day and a devoted mother, who, despite punishing filming schedules, drove her children to school.

But then it was not the first time that a role created rumors that blurred into the actress' real life. She once played a patient with an incurable disease and rumors spread that she was really sick. According to a representative from her agency, rumors must start because her performances are so great that audiences confuse fiction and reality.

In real life, Kim Hee Ae has been married to her husband Lee Chan Jin, a software engineer and CEO of the DreamWiz portal, for 17 years.

On a recent episode of "Healing Camp," the actress talked honestly about her husband and their life together. It was not picture-book-perfect but it was a successful marriage.

""Married life is not just about being happy," said Kim Hee Ae. "There are a lot of hard times as well."

She also confessed that she does not really know what software engineers do.

"I was introduced to my husband by his older brother, but I did not know exactly what he did for a living and I still don't think I know."

On "Noonas Over Flowers," she said she married her husband because he looked intelligent. She remembered seeing a couple on a plane that talked the entire night with a laptop in front of them. That seemed to her an ideal marriage.

When she first met her husband he did not have a car so she had to pick him up. He got into the passenger seat and took out his laptop. When he began to type on it, she thought he looked intelligent and that won her heart. The couple married after dating for three months.

As convincing as the steamy chemistry between the "Secret Love Affair" co-stars is, Kim Hee Ae's marriage is still going strong.