Whenaseriesofpackagebombsshowuponthedoorstepsofprominentpoliticiansandbusines求爱eninthesummerof1919,U.S.BureauofInvestigationAgentWilliamFlynn(Strathairn)isassignedthetaskoffindingthoseresponsible.Hebecomesimmersedinaninvestigationthatuncoversananarchistplottodestroydemocracy.