"Valentino: Master of Couture" at Somerset House on the River Thames in central London features more than 130 pieces from a designer whose clients included Grace Kelly, Jackie Kennedy Onassis, Elizabeth Taylor and Princess Margaret.
Dressed in a light grey suit and lilac shirt, the man simply referred to in the industry as Valentino told reporters he hoped to do more shows in England in the future.
"I love England, I love to be in London and I hope to be able to come very often to do other exhibitions, other Valentino things in this beautiful city," he said.
Besides the black velvet evening gown with white ribbons Roberts wore when she won the best actress Oscar and a delicate floral dress with green sash designed for Hepburn, the exhibition delves into Valentino's personal letters and photographs, displays handcrafted couture gowns and has digital installations, including videos of his atelier.
Upon entering, visitors are greeted by a huge white flower installation with interactive projections and quirky display cases made of plush white upholstered chairs.
A pale lilac carpet on the next level leads visitors towards a catwalk, where rows of white chairs are lined up amongst more than 130 pieces from Valentino's couture collections.
"We want visitors to feel in the centre of things on the catwalk, so it's a privileged catwalk in a sense...We hope it's going to be a really pleasurable experience," co-curator Alistair O'Neill told Reuters.
Mannequins, sporting blonde wigs in different hairstyles, are dressed in decadent evening gowns with ruffled floral details, in the designer's signature red, as well as black, soft creams and animal prints.
The exhibition took around a year and a half to assemble, said O'Neill, who co-curated the show alongside Patrick Kinmouth and Antonio Monfredo.
The collection also features sleek capes, brightly colored kaftans and chic day dresses which span Valentino's work over the past 50 years.
"We wanted to be able to show something of this very rarefied world," O'Neill said.
"It's very normal for Mr. Valentino...but for us, it's an amazing thing to step into."
(Reporting by Li-mei Hoang, editing by Paul Casciato)
