Rocca and his nine gladiators have just completed a triumphal show in the arena in front of the Emperor. However their ebullient mood changes to horror and sadness when they are followed by a group of a dozen gladiators from Thrace who are ordered to kill each other until one man is standing. In this group is a father and son. They reluctantly comply but when the son faces his father one of the gladiators steps in to prevent the son from killing his father then throws his sword at the Emperor's box.