Mrs Ada Harris is a cheery London charlady earning an honest living cleaning the homes of the well-to-do. Hers is a simple humble life – so she can’t quite believe her luck when she wins a once-in-a-lifetime trip to Moscow. With her dear friend Mrs Butterworth in tow, Mrs Harris is determined to use her holiday to reunite her lovelorn employer Geoffrey Lockwood with a Russian lady he loved years ago. Unfortunately, the discreet passing of documents is an activity that can land even the most well-intentioned old ladies in hot water with the KGB!