The actress, 25, looked stunning in an emerald tulle gown by Valentino. The full-length outfit featured a plunging neckline and criss-cross back and also had a knotted tie at the waist, reported Us magazine.
Stone had chopped off inches of her auburn locks into a textured choppy 'do crafted by her celeb stylist Mara Roszak.
She complemented the dramatic look with berry shades of make-up.
While Stone is cutting her hair, boyfriend Andrew Garfield is letting his grow. He showed off a full-on mountain man beard while arriving at the Italian city early this week.