The story of 14-year-old Tamara Eremenko, who finds herself on the brink of survival in besieged Leningrad in the winter of 1942. A convoy of mail trucks arrives in the city for the first time in months. The Main Post Office is desperately short of mail carriers. To survive the winter and save her sister, Tamara must deliver six letters and prove her fitness for the job, only to be hired as a postman.