Winnie is desperate and doesn't know what to do next. She is about to marry her lover Paul, who has returned from war captivity. Both want to emigrate to America short after marriage. But the young woman has an illegitimate one-and-a-half-year-old son, whom she has kept secret from her fiancé. The short-tempered Paul would never understand that. When she is on her way to the orphanage, the grumpy senior civil servant Hieronymus Spitz and his little dog Tobby get into her train compartment. After a short observation, Winnie is certain that the misantrope actually has a good heart, because he lovingly takes care of his dog. Without further ado she leaves little Niki with the tax accountant and disappears from the train. Only a note with a request remains. The overwhelmed old gentleman initially wants to get rid of the child, but then takes it home and takes care of it together with his housekeeper. Both take the bundle of joy to their hearts. But then everything turns out differently.
