In the distant future, humanity has explored beyond Earth and colonized both the inner and outer planets of the Solar System. In order to protect the colonies and maintain law and order in the solar system, the Earth Federation Government (EFG) was created. Soon, many settlers started to resent the EFG's and its sphere of influence, straining the relationship between the central government and the colonies.
The Star Sheriffs are sent to protect a computer controlled cosmos freighter from Outrider attacks. However, they arrive too late and find the freighter destroyed, and only one survivor: a young girl named Annabelle.
April's uncle Wayde is revealed to be a secret agent who has been smuggling information about the new Outrider hideout to Cavalry Command. The Star Sheriffs are sent to help him reach his destination safely.
The Star Sheriffs arrive in a territory outside their jurisdiction, the Kingdom of Jar. The King reluctantly tells them that they do not need help from Cavalry Command anymore, even though they are still under constant.