Adapted from the popular stage play of the same name, Dear Ruth features Mona Freeman as teenaged Miriam Watkins, who can't keep her nose out of other people's affairs. Fired up by patriotism, Miriam inaugurates a warm pen-pal relationship with an overseas air force officer (William Holden), hinting at a future marriage. When the airman arrives in town, he insists upon seeing Miriam's older sister Ruth (Joan Caulfield). It seems that Miriam, in an effort to appear older, signed her letters with her sister's name, and even enclosed her sister's picture. Ruth, however, is engaged to her nerdish employer (Billy DeWolfe), and it isn't hard to imagine the plot convolutions that ensue from this set-up. Dear Ruth was written by Norman Krasna, who based the Watkins household on the family of his old friend Groucho Marx (whose first wife's name was Ruth).
by Hal Erickson synopsis