The Diamond Queen is a 1921 American adventure film serial directed by Edward A. Kull. The film is considered to be lost. The creator of the story Jacques Futrelle was lost in the Titanic] disaster in 1912.
College athlete Jimmy Brent (Larkin) is sent to Wyoming to beat up Big Bob Phillips, his uncle's rival for the hand of Mary Allen. When Jimmy arrives in Wyoming, he falls in love with Gloria Phillips (Love), and decides not to beat up Phillips. When Phillips mistakenly thinks that Jimmy is the cause of cattle rustling, Jimmy fights Phillips, catches the actual cattle rustlers, and gets the girl.