What really goes on inside Vogue magazine's offices? The famous top-fashion magazine, known to many fashion-conscious Americans as "the Bible of fashion," has gained the reputation of being cutthroat and harsh, yet the best of the best fashion magazines.

If you're really very curious as to what happens day to day at Vogue magazine, you're in luck. "The September Issue," a documentary chronicling eight months inside Vogue's offices working on Vogue's biggest issue of the year (that would be the September issue), will premier this weekend at the Sundance Film Festival.

Director R.J. Cutler didn't have any boundaries when filming, he told Women's Wear Daily, and had unlimited access to Anna Wintour and her editorial and fashion team. "My observation with the creativity in the hallways and offices is that Vogue is like the mist," Cutler told WWD. "You don't think it's raining and all of a sudden you're soaking wet."

The film was created from about 300 hours of footage, and even has Wintour's stamp of approval - not an easy feat. "I'm thrilled she's supporting the film, which is a reflection of how she feels about it," Cutler said.

According to Cutler, it was Wintour's idea to center the film around the creation of Vogue's September 2007 issue. As it turned out, the film also chronicles the last days of a better economy.

The movie also follows Wintour's relationships with her late father, British newspaper editor Charles Wintour, daughter Bee Shaffer and creative director Grace Coddington. Several prominent fashion designers make guest appearances in the movie as well, including Karl Lagerfeld, Thakoon Panichgul and Oscar de la Renta.