Fashion A-List 5/31 Top Looks of the Week By InStyle Editors InStyle Editors Facebook Instagram Twitter Our editors and writers comprise decades of expertise across the beauty, fashion, lifestyle and wellness spaces in print and digital. We prioritize journalistic integrity, factual accuracy, and also having fun with every story we share. InStyle's editorial guidelines Updated on March 24, 2015 @ 04:44PM Pin Share Tweet Email Trending Videos Photo: Randy Brooke/WireImage A-List 5/31 Top Looks of the Week 01 of 22 Jessica Chastain Venturelli/WireImage WHAT SHE WORE Jessica Chastain raised a glass at a Fondazione Nicola Trussardi cocktail party in a geometric Trussardi sheath, ladylike bag and leather Louboutins. WHY WE LOVE IT This print can't be missed! The actress looked striking in her bold black and white design. 02 of 22 Christina Ricci Michael N. Todaro/WireImage WHAT SHE WORE Ricci supported the Fresh Air Fund in a peek-a-boo Thakoon cocktail dress and gold stilettos. 03 of 22 Emmy Rossum Michael Kovac/WireImage WHAT SHE WORE Rossum attended the Emmy Studio in a pleated Bibhu Mohapatra print dress and pointy-toe Benjamin Adams London heels. 04 of 22 Kerry Washington Michael Kovac/WireImage WHAT SHE WORE Washington toted a chainstrap Roger Vivier bag with her black Calvin Klein Collection shift and leopard print pumps at the Variety Emmy Studio. 05 of 22 Rose Byrne Broadimage Newswire WHAT SHE WORE Rose Byrne was pretty in Emilio Pucci's long-sleeve minidress, delicate Jennifer Meyer rings and satin Salvatore Ferragamo pumps at the L.A. premiere of The Internship. WHY WE LOVE IT Sweet and sexy! Sheer point d'esprit panels added seductive appeal to the actress's pastel wool dress. 06 of 22 Naomie Harris Dave M. Benett/Getty Images WHAT SHE WORE Harris took in a polo match in a floral Dolce & Gabbana needlepoint sheath and pastel stilettos. 07 of 22 Cameron Diaz FameFlynet, Inc WHAT SHE WORE Cameron Diaz was white hot in a curve-hugging Roland Mouret design and ankle-strap sandals at a Monaco Tag Heuer bash. WHY WE LOVE IT A crisp hue complemented the actress's signature bronze glow! 08 of 22 Hilary Swank www.bauergriffinonline.com WHAT SHE WORE From dress to shoes, Swank was decked in Giambattista Valli at Vienna's Life Ball. 09 of 22 Heidi Klum Landov WHAT SHE WORE At a press event for Germany's Next Top Model, Klum was at her sexiest in a black and gold Atelier Versace ensemble. 10 of 22 Nicole Kidman Matt Baron/BEImages WHAT SHE WORE Nicole Kidman sparkled in a silk Giorgio Armani column and diamond Harry Winston jewels at the Cannes closing ceremony. WHY WE LOVE IT Way to go out with a bang! The festival juror wrapped things up in her most glam gown. 11 of 22 Berenice Bejo Vittorio Zunino Celotto/Getty Images WHAT SHE WORE Berenice Bejo attended the Cannes Zulu premiere in an embroidered Elie Saab cocktail dress, sparkling minaudiere and suede pumps. 12 of 22 Olivia Palermo Oraito/Splash News WHAT SHE WORE Palermo glowed on the Cannes red carpet in a gold Roberto Cavalli ensemble that she paired with a complementary bracelet and plumed clutch. 13 of 22 Marion Cotillard Matt Baron/BEImage WHAT SHE WORE Cotillard accented her long-sleeve Dior column with diamond Chopard jewels at the Cannes Film Festival premiere of The Immigrant. 14 of 22 Uma Thurman Jerocki/Guignebourg/News Pictures/iPhoto WHAT SHE WORE Thurman dined with the Cannes winners in a custom navy blue Giorgio Armani gown, statement jewels and flat Jimmy Choo sandals. 15 of 22 Rosie Huntington-Whiteley News Pictures/iPhoto WHAT SHE WORE In Cannes, Rosie Huntington-Whiteley took in the view wearing a pastel Chloe skirt, embroidered cotton blouse, python clutch and patent leather Brian Atwood pumps. WHY WE LOVE IT Who would't want to look like this? The model looked effortlessly stylish in crisp separates. 16 of 22 Brooklyn Decker Frank Micelotts/Invision for Twentieth Century Fox Television/AP WHAT SHE WORE Decker screened Lot Party in a botanical print dress and sparkling sandals. 17 of 22 Minka Kelly Michael Kovac/WireImage WHAT SHE WORE At a Beverly Hilton pool party, Kelly accented her plunging Dior LBD with a diamond EF Collection bracelet and bright Jimmy Choo pumps. 18 of 22 Jessica Biel Gotcha Images / Splash News WHAT SHE WORE Biel stepped out in Cannes wearing a color block Roksanda Ilincic sheath, a complementary clutch and pointy-toe Louboutins. 19 of 22 Isla Fisher Jonathan Leibson/WireImage WHAT SHE WORE At the Hollywood screening of Now Your See Me, Fisher paired her embellished Sachin + Babi sheath with patent leather platforms. 20 of 22 Gwyneth Paltrow David M. Benett/Getty WHAT SHE WORE Gwyneth Paltrow kicked off summer at a Goop bash wearing a silk charmeuse shirt dress and leather belt from Prabal Gurung and edgy sandals. WHY WE LOVE IT Nothing says "summer" like a fresh print and lightweight fabrics! 21 of 22 Stacy Keibler Neilson Barnard/Getty WHAT SHE WORE Keibler raised a glass to Stella Artois in an asymmetric red dress and studded pumps. 22 of 22 Emma Roberts Randy Brooke/WireImage WHAT SHE WORE Roberts feted the Intermix 20th anniversary in a form-fitting Ohne Titel sheath and black accessories, including suede Jean-Michel Cazabat booties.