After the death of their father three sisters, sixteen year old Lou, Charly who is in her early twenties and Emmie who is a mere child, have to try and run the family's horse farm between them. They have to overcome all manner of adversity in order to keep their beloved farm.

When a poison attack is made on the racehorse Cagliostro, Lou flees the Immenhof with the horse. Together they find refuge with Cal, who lives away from civilization with his semi-wild horses. In his new home, Lou makes the horse promise that it will never have to take part in a race again. However, this is by no means the end of the threat to Cagliostro.