Four bladesmiths are in for a workout when they are tasked with forging signature blades from gym equipment. The competitors flex their skills, battling forge welding failures and warps. After a severe round of testing, the two remaining smiths have only four days in their home forges to recreate one of Japan's deadliest swords: the Nagamaki. Who will master every detail of this giant weapon and emerge as the Forged in Fire Champion, earning the $10,000 prize?