To Catch a Thief is a 1955 American romantic thriller film directed by Alfred Hitchcock, from a screenplay by John Michael Hayes based on the 1952 novel of the same name by David Dodge. The film stars Cary Grant as a retired cat burglar who has to save his reformed reputation by catching an impostor preying on the wealthy tourists of the French Riviera. Grace Kelly stars opposite him as his romantic interest in her final film with Hitchcock.

In the film To Catch a Thief by Alfred Hitchcock, Grace Kelly as Frances Stevens, a spoiled American girl from a rich family has just met John Robie the jewel thief(played by Cary Grant). They are going out, Robbie is waiting for Frances in the lobby. And when she makes her appearance down the lobby, everyone stop chatting or walking and start looking at her: She is wearing a black halter neck swimming suit with a pair of black capri pants ruched up, matching with her black turban and black wedged sandals, her all-black outfit is then framed by pure white: a white brimmed crown-less fine straw hat on the black turban, and a white linen wrap skirt covering her capri pants.

In the blog Clothes on film, the writer has used words like absurd and childish to describe her outfit. But there is nothing childish or absurd about this stunning and genious beach ensemble designed by Edith Head, and one of the best things about the design is how the costume designer has made Grace's white linen skirt just a little longer than her black capri pants to create the illusion of her wearing just a black body and a white skirt while looking from far away, like the character France played by Grace Kelly, she gives the illusion of someone but reveals herself only up close, really up close. 

And in her prime time, whether on screen or off-screen, Grace Kelly never looks absurd or childish, with her inner grace, she can carry off almost any outfit. Even a pair of rolled up jeans A LA capri pants, which could plain on others, look graceful on her, whether pairing with ballet flats or loafer.

Unlike Audrey Hepburn, Grace Kelly's name is not so closely linked to black dress. We can remember her in icy blue, minty green, pure white or even fire red, but not so much in a black dress. The two most famous black dresses she wore on screen are the one she wore in films The Country Girl(1954) and Rear Window(1954). Both films were released in the same year, and both black dresses are of the same style: V neckline, cap sleeve, flared skirt, and Grace Kelly wore the two dresses with the same accessories: pearl earrings and necklace.

​That seems to be her favorite style of black dress, which she since then carried in her private life in different versions. The most publicized black dress Grace Kelly wore off-screen was in 1955, on Cannes Film Festival. It was the same silhouette, again with V neckline and flared skirt, again worn with pearl necklace. She was then still with French actor Jean-Pierre Aumont. Just a few days later, Grace Kelly met Prince Rainier of Monaco. A year later, she was married to him.

After becoming Princess of Monaco, the few black dresses she carried were of slimmer silhouette, mostly column shape, and the neckline became higher. But she still wore the pearl necklace with the black dresses, sometimes.