Romantic dreamer and aspiring stockbroker Edward Robinson is engaged to practical and prosaic Maud Lithinglow. When he wins five hundred pounds in a competition, he secretly purchases his heart's delight, a white Riley sportscar. At Christmas time he motors alone down to Brighton where he meets Lady Noreen Elliot, who is similarly engaged to an unadventurous partner. For one glorious, heady evening Edward mixes it with the Bright Young People, becoming involved in the theft of a priceless diamond necklace and dancing at The Cafe de Paris with Lady Noreen. In the course of one evening Edward becomes a man, instead of a mouse, and when morning arrives it is a different Edward who confronts Maud with his new car, expensive engagement ring and marriage plans. (thetvdb.com)