Isaac Mizrahi and Derek Blasberg at W New York Downtown.

Last night, a group a fashion moguls, designers, models and perfectly dressed men and women, made their way to the W New York Downtown hotel to view the first film screening in in the Grand Classics series "New York in Film."

The evening commenced with a cocktail hour, rife with fashion editors and a lingering music crowd. It was a fitting precursor to the film screening of Sweet Charity–a personal pick by Isaac Mizrahi, a New York fashion icon who knows all about sexy.

“There’s a difference between when you put air quotes around something, and it’s actual meaning, you know what I mean? So it’s like 'sexy' is not as good as sexy, and this is a really sexy movie,” Mr. Mizrahi told The Observer, sincerely.

As if almost on cue, a 20-something woman donning a black dress and crimson pout fluttered up to Mr. Mizrahi, obviously inviting some sort of approval for her carefully pieced-together ensemble.

And Mr. Mizrahi didn’t look too bad himself–not that we expected anything less. A classic black button-down with a mandarin collar gave a very classy vibe and a nod to the 1960’s styling of Sweet Charity.

Lavish hors d’oeurves circulated through the W Downtown’s fifth-floor lounge at the same rate drinks were poured. We expected a strictly early 20’s crowd given the loud, techno-y music played by the DJ, Eiko. Not the case. The younger crowd meshed seamlessly with a more mature circle of hotel guests and those already familiar with nightlife in the financial district.

And with an overabundance of sky-high heels and perfectly manicured blowouts laying siege to the plush seating, we could easily spot what the allure was.

Mr. Mizrahi shifted his attention away from the young woman and back to us.

The film, he said, reflects New York at a time when it was less glamorous and the famous were less dependent on stylists–New York fashion in its rawest form.

Katrina Plavos helped to launch Grand Classics to highlight films that inspire fashion icons and directors in New York City. Ms. Plavos said the program was introduced after 9/11 to bring “spirit and joy back to New York.”

Her only stipulation for Mr. Mizrahi’s film choice was that it had to take place in New York. Sweet Charity highlights the life of a dance hall hostess, Charity Hope Valentine, played by Shirley MacLaine, who finds love (or lust) with all the wrong men.

“It really is about a bygone New York. It is about this ideal that I grew up loving about New York; this incredible presence of contrast,” Mr. Mizrahi told us, talking as though he’s experienced a close kinship with the area.

“And also, the clothes. Oh, the clothes,” he gushed. “You think you’ve seen a trench coat, you think you’ve seen a trench coat with an edge and then you see Sweet Charity.”

Guests eventually migrated away from the cocktail lounge, drinks still in hand, to view the screening from W’s 31st floor, which boasted a 360-degree view of the city skyline and the Hudson River, offering a peek at both the Statue of Liberty and Empire State Building.

After Derek Blasburg, fashion writer and editor, introduced Mr. Mizrahi to the room, guests noshed on a 1960s-themed candy bar of spiced popcorn, M&Ms and Charleston Chews among other treats.

Just before the film began, Mr. Mizrahi left guests with one final sentiment of Sweet Charity.

“It’s gritty and rough and there are maybe bad parts of it,” he said. “But it’s mostly amazing.”