By Sharon Clott Kanter
Updated Oct 08, 2012 @ 11:34 am
Credit: WireImage; Getty Images

It was a fashion double-take at the Hamptons International Film Festival this weekend, where Sienna Miller celebrated her new film, The Girl, in a white dress with cape-like sleeves by Alessandra Rich, a fellow Brit who launched her line in 2009. "I'm happy to support a new designer," the actress—in her first post-baby appearance—told The look reminded us of Gwyneth Paltrow’s statement-making Tom Ford gown for this year's Oscars. (They both even accessorized with big cuffs!) "The Oscars is the biggest nail-biter," Paltrow had told us of this look. "I've learned to wear what works for my body while always taking a bit of a risk. This Tom Ford gown was stunning and modern and recalled a kind of '60s glamour." Do you like the cape style? Let us know!

Plus, see Sienna's best looks ever.