King Bohlem, brother of the late Attila, reconquers former Hun territory. To secure this territory, he sends his son, Otto, and his nephew, Tharus, to forge an alliance with King Haadem, strongest of the neighboring rulers. Haadem, however, is just concluding an alliance with Kudrum, the ambitious son of a king hostile to Hun interests. To cement this alliance, Haadem has agreed to marry his daughter, Tamall, to Kudrun, but Tamall dislikes Kudrum. She quickly falls in love with the newly-arrived Tharus. Kudrum inflames Haadem's feelings against Tharus and arranges to have Tharus publicly flogged. Not satisfied, Kudrum then murders Haadem and has the crime blamed on Tharus. Tamall's love for Tharus is tested but then she comes to believe Tharus's claims of innocence and works on behalf of Tharus as Kudrum's forces arrive for a decisive battle.

Marco Trevisan returns to his hometown hoping to be greeted with a welcome party but is instead attacked and captured by Turkish pirates led by the brutal Rabanek.