Duchess of Idaho (1950)

Ellen Hallet is in love with her playboy boss, Douglas Morrison, but too timid to do anything about it. Her roommate Chris devises a plan to help her: she follows Morrison on his trip to Sun Valley, Idaho and plays the overattentive female, hoping he'll send for Ellen, who often plays his "fiancée" when he has a female he can't discourage otherwise. Complications arise when Chris catches the eye of band leader Dick Layn and lands in a triangle with the two men.