A man tries to avenge the death of his sister, a gambling addict. Another man, an ex-convict who whistles when he commits a crime, is reunited with his blind mother.
A murderer terrorizes the city of Buenos Aires by attacking on the streets on rainy days and always leaving a card with the name "S. López". A local boarding house full of eccentrics appears to house a possible suspect.
The film narrates events of the Revolution of the Park, carried out by radical sympathizers on July 26, 1890. There is a secondary plot with the romance of a girl who, despite being in love with her father's godson, must contract a marriage with a banker that fails.