Long Island fashion designer Elene Cassis prepares for Fashion Week...

Long Island fashion designer Elene Cassis prepares for Fashion Week from her studio in New York City. (September 3, 2010) Credit: Photo by Jin Lee

Debuting at Mercedes-Benz Fashion Week can be nerve-racking, but when Oscar de la Renta switches his show last minute to your same day and time - well, that could send dizzier, diva-like designers over the edge.

But not Elene Cassis.

It's taken the St. James native a long time to get here. And she's overcome a lot worse.

Like the day in 2001 when she heard a wailing scream coming from over the bluff behind her parents' house. Still in her pajamas, she ran out to the nearby beach on Long Island Sound. "I saw my dad lying half in the water and half out," she recalls. Her father, who owned the Camelot and Excalibur diners on Jericho Turnpike, had been in his boat with a friend. Now, the friend was pounding on his chest, trying to revive him. She ran to call 911, but it was too late.

In the years after her father's death, "I was lost . . . so lost," she says. She canceled plans to move to Manhattan, stayed home to help her mom raise her younger sister and killed time doing real estate. It wasn't till she saw "Project Runway's" Tim Gunn on an episode of "Martha Stewart" that she thought, on a whim, "maybe I could do that."

So she went back to school, graduating last year with a fashion degree from Parson's. Since then, Cassis, now 34, has been making up for lost time: She started her own label, designed two dress collections, opened a showroom, coaxed celebs (including Jennifer Love Hewitt and Katy Perry) into her dresses, and Thursday, Sept. 16, she launches her first runway show at Fashion Week.

Priced $300 to $500, the shifts, tunics and strapless numbers are all black and white, with clean, architectural lines. The Kathleen, named for an aunt, is a black wool bouclé sleeveless with a single white stripe. Think Jackie O. Or Michelle Obama, for that matter.

"It's not glamorous," she says, explaining how she drags racks of dresses across crowded city streets. As for de la Renta's show?

"There's no perfect time," she says, noting that if she switched days, she'd be up against other heavy hitters, like Calvin Klein.

"This is what I was meant to do in life," she says. "Once you find your true passion, every negative can be thrown at you, but it doesn't matter - you keep going."