In 1796 Bow Street Runner and amateur pugilist Dan Foster is sent to Somerset to infiltrate a poaching gang suspected of murdering Lord Oldfield’s gamekeeper, Josh Castle. Dan has walked into a volatile situation: the locals are up in arms against Lord Oldfield for enclosing Barcombe Forest and depriving them of their rights to gather fuel and food.
Against a background of vandalism, arson and riot, Dan discovers that there were others with a grudge against Josh. However, Lord Oldfield orders him to arrest the poachers. When Dan learns that Josh had a claim to the Oldfield estate his suspicions focus on Lord Oldfield. Before he can confront him, rioters attack Oldfield Hall protesting against the arrests. During the fight, Dan finds himself at the mercy of the local doctor and realises that he and Josh were rivals in love. Dan narrowly escapes death and arrests the murderer: Doctor Russell.