Samson and Delilah (1949)
worn by Hedy Lamarr as Delilah
by Edith Head

Although it looks like a dress on the mannequin it’s actually two pieces, a bra style top and skirt.
Edith Head won the Academy Award for Best Costume Design for her work on this film.

The Bride Wore Red (1937)
Iconic red bugle bead gown worn by Joan Crawford as Anni Pavlovitch 
by Adrian 

Forbidden Planet (1956)
flesh colored mini dress worn by Anne Francis as Altaira
by Helen Rose 

Pink Floyd The Wall (1982)

Mask from one of the most memorable scenes from the movie set to Another Brick In The Wall (Part 2) worn by one students as they go through the school and eventually into the meat grinder.

Saigon (1947)
Gown worn by Veronica Lake as Susan Cleaver
by Edith Head 

The Wizard Of Oz (1939)
Margaret Hamilton’s Wicked Witch of the West hat
by Adrian 

The hat was designed with an offset cone and noticeably irregular brim to dip over the witches face and create shadows to make her appear more menacing. This version of the hat was used throughout the film, but most prominently in the melting sequence.

The Wizard Of Oz (1939)
Margaret Hamilton’s Wicked Witch of the West hat
by Adrian 

The Great Man’s Lady (1942)
Worn by Barbara Stanwyck as Hannah Sempler
by Edith Head

To me the dress looks like it’s at least partly inspired by one designed by Adrian for Greta Garbo in the movie Camille.

To Catch A Theif (1955)
worn by Grace Kelly as Frances Stevens in the costume ball scenes
by Edith Head