In "American Ninja 5," a young boy named Hiro discovers an ancient Japanese medallion that grants him incredible ninja powers. With his newfound abilities, Hiro must save his grandfather, a martial arts master, from an evil businessman who seeks the medallion's power for his own sinister plans. Along the way, Hiro teams up with Joe, a former American ninja, who helps him navigate the dangerous world of ninjas and bring down the villainous forces. Together, they embark on an action-packed adventure filled with thrilling fights, intense training, and a race against time to protect the ancient power of the medallion and restore honor to the ninja legacy.