My how they've changed! Cast of Lena Dunham's hit HBO show Girls transform into high-fashion stars at season premiere

From a newly blonde Lanvin-clad Zosia Mamet to Jemima Kirke and Allison Williams in Altuzarra, and Lena Dunham in Valentino, the cast of Girls seem to have found their fashion-feet since the shows' first season.
On the red carpet at the Girls season two premiere last night, the glamorously-groomed four cast members radiated confidence - a far cry from the awkward boho-luxe looks they sported last year.
Miss Kirke, 27, who plays Jessa on the show, joked to Style.com: 'I mean, we're all wearing black. I think we're all really taking ourselves very seriously now.'

You go, Girls: (from left) A newly blonde Lanvin-clad Zosia Mamet, Jemima Kirke and Allison Williams in Altuzarra, and Lena Dunham in Valentino

Season one: The Girls cast on the catwalk at the show's pilot premiere a year ago

Proving that the glamour won't take away from the fun, however, Miss Dunham, the show's creator and writer, told Vogue.com: 'I’m not wearing underpants. It’s very liberating.'

The 26-year-old was wearing a Valentino jumpsuit, fastened with a large white bow at the back.
She admitted of her red-carpet moment: 'I had some professional assistance, recommending I do an over-the-shoulder shot.

From awkward to awesome: Lena Dunham, the show's creator and writer, at the pilot premiere last year (left) and at last night's season two premiere (right)

Mimi Mamet: Zosia Mamet, 24, stayed with an above-the-knee dress, but went from a cap-sleeve blue dress into the evening with a ruffled Lanvin number from the fall 2012 collection

Velvet love: Jemima Kirke, 27, went from last year's green boho velvet (left) to sophisticated black (right)

Favourite silhouette: Allison Williams, 24, opted for a similar strapless pencil skirt dress from last year (left); but for the season two premiere her Altuzurra dress gave a glamorous grown up vibe (right)

'That is not in my personal arsenal, but I tried to do it the best I could.'

Miss Mamet, 24, who plays Shoshana, was the most obviously transformed, however.
Her hair was freshly honey blonde, a week-old look that she took on for a role in a play called Really Really.

Glamour shot: Miss Dunham, 26, admitted of her red-carpet moment: 'I had some professional assistance, recommending I do an over-the-shoulder shot

Glamour Girls: Miss Mamet, 24, who plays Shoshana on the show, was the most obviously transformed with freshly honey blonde hair (far left)

Celebration kisses: Actor Andrew Rannells, who plays Hannah's ex-boyfriend in the show, and Miss Williams , 24, seal  season two with a kiss

She said of her striking Lanvin dress, from the fall 2012 collection which is in store now: 'Dude, I love a ruffle. I am a very non-girlie human, but something about a ruffle can be rock ’n’ roll - if you can wear the ruffle and not let it wear you.'
Allison Williams, 24, who plays the tightly-wound Marnie, wore a strapless dress like last year, but this time it was a black embellished with gold Altuzarra number.
Designer Joseph Altuzzura attended the premiere, as did many other fashion folk, including designer Cynthia Rowley, model Hilary Rhoda, and J crew's Jenna Lyons.