OAKBROOK TERRACE, Ill.—It’s no easy thing to adapt a movie into a stage play. A movie can use lavish background sets and fascinating locations that are unavailable to the theater. In a film, everything can be stopped, re-filmed, and edited post production, while in theater you can’t just stop the action and try again if actors make a mistake. The action in film is told in images while in theater, primarily, images have to be converted into dialogue. A film is a recording that has already happened while theater happens in the here and now.
Those are some of the reasons that cinema is a much safer medium than theater, and why “The 39 Steps,” now playing at the Drury Lane Theatre, is such an inventive accomplishment.