“We entered Cosprop as ourselves and walked out as the person we were playing,” says Helen Bonham Carter. Founded in 1965 by the designer John Bright, Cosprop has since made some of the most recognizable period costumes in theater, film, and television history. From A Room with a View and Out of Africa to Downton Abbey and The Crown, the company’s work is now the subject of an exhibition. Accompanied by an illustrated book with a foreword by Judi Dench, the show presents ensembles that visitors will instantly recognize as well as pieces never before shown in public. —Jeanne Malle