From the lavish productions of Hollywood's Golden Age through the high-tech blockbusters of today, the most memorable movies all have one thing in common: they rely on the magical transformations rendered by the costume designer. Whether spectacular or subtle, elaborate or barely there, a movie costume must be more than merely a perfect fit. Each costume speaks a language all its own, communicating mood, personality, and setting, and propelling the action of the movie as much as a scripted line or synthetic clap of thunder. More than a few acting careers have been launched on the basis of an unforgettable costume, and many an era defined by the intuition of a costume designer—think curvy Mae West in I'm No Angel (Travis Banton, costume designer), Judy Garland in A Star is Born (Jean Louis and Irene Sharaff, costume designers), Diane Keaton in Annie Hall (Ruth Morley, costume designer), or Harrison Ford as Indiana Jones in Raiders of the Lost Ark (Deborah Nadoolman Landis, costume...