 In the middle of a pictorial lecture on his recent expedition to the Mongolian Desert, Dr. John Benton (Charles Miller) the famous explorer, drinks from the water bottle on his lecture table, collapses and dies. His last words "Eternal Fire" are the only clue Chinese detective Jimmy Wong (Keye Luke) and Captain Street (Grant Withers) of the police department have to work on. Win Len (Lotus Long), Benton s secretary, reveals the doctor s dying words refer to a scroll which tells the location of rich oil deposits. Wong and Street then begin the search for the killer among Benton s associates.