Dick Grayson operates as Nightwing in the animated film, a former Robin who forged his own heroic identity distinct from Batman. He joins a group of heroes and villains transported from modern Gotham City to feudal Japan by Gorilla Grodd's time displacement machine. Nightwing and the Bat-Family arrived two years prior to Batman's own arrival. Upon reaching the past, the Bat Clan of Hida, adhering to a prophecy about a foreign bat ninja restoring order, aided Nightwing, Red Hood, Red Robin, and Robin. Guided by the Bat Clan, Nightwing mastered ninjutsu, becoming a highly skilled practitioner. He adopted the era's traditional weaponry and combat techniques, wielding twin escrima sticks as his primary weapons.

A seasoned leader and strategist, Nightwing coordinates closely with the Bat-Family and the Bat Clan. He battles the transformed Gotham villains who seized power as feudal lords, participating in critical confrontations like the clash at the "Field of Hell." There, he fights alongside allies to defeat the villains and opposes Gorilla Grodd's attempt to control them. Nightwing remains instrumental in the final battle against the Joker's merged super robot, Lord Joker. When Robin commands an army of monkeys using a flute, Nightwing supports the strategy leading to the creation of the "Batgod," a giant samurai monkey fused with a swarm of bats. This entity confronts Lord Joker, enabling Batman to engage the Joker directly. Following victory, Nightwing assists in restoring order to feudal Japan before returning the captured villains to the present day with the Bat-Family.

His character maintains core comic book traits: exceptional martial prowess, leadership, and a strong sense of justice. He operates with a degree of independence while remaining a committed Bat-Family member. His adaptation to the feudal setting demonstrates resilience and skill, utilizing his acrobatic expertise and combat mastery within the context of ninja warfare.