Seyfried and Hayek both chose Alexander McQueen gowns featuring the once-popular halter neckline for Hollywood's biggest night of the year.
"This was the one from the very beginning," the Les Miserables star said of her gown choice, a lilac organza design featuring silver dragonfly embroidery.
Hayek, on the other hand, went with a much more dramatic look, wearing a deep midnight blue velvet gown that showcased a heavily embellished collar, dripping in gold.
Roberts also opted for velvet, stunning fans in a halter neck Marc Bouwer frock in royal blue with a keyhole opening and matching sapphire earrings.
What do you think of the '90s flashback?