A tramp cares for a boy after he's abandoned as a newborn by his mother. Later the mother has a change of heart and aches to be reunited with her son.
Just charming. Arguably no overt villains (save, of course, the system of crushing poverty and the social mores that led the mother to give up the kid in the first place...). Can't quite decide whether the dream sequence is a positive or negative addition to the film, but frankly, who am I to second guess Charlie Chaplin?