We last see Dick Grayson at Amy Rohrbach's funeral. This movie takes place the next night. He puts on his old Robin costume and goes on patrol. The 1st few nights, he stops a few petty crimes and gets mocked by the criminals every time for bein "Batman's B*tch". He decides he needs a new persona to instill fear into all his enemies. He goes and gets material to make a new suit. Meanwhile, Roland Desmond's brother, Mark, a brilliant scientist is doing experiments. During one of his experiments, he hears something and looks around and sees nothing. He is holding a chemical and sees a man in front of him and out of fright drops the chemical on himself. The man turns out to be Roland Desmond who just broke out of jail. The chemical turns Mark Desmond into a tall, muscular, mindless behemoth. Roland realizes he can use his brother to commit crimes. Roland and his brother, whom Roland calls Blockbuster now, go on a major crime spree. While this is happening, Dick makes his new costume and renames himself Nightwing. Nightwing starts to investigate the crimes Roland and Blockbuster have been committing. Nightwing discovers where the next crime will be committed and waits for them to come. Nightwing fights Roland and Blockbuster but is completely manhandled. He realizes he needs help and decides to swallow his pride for the better good and contacts Batman and Batgirl to come help him defeat The Desmonds. Batman, Batgirl, and Nightwing patrol together and find the Desmonds. In this scene, Batman, Batgirl, and Nightwing defeat Blockbuster in a fight to the death. During this Roland Desmond gets away. This showing his total evilness by having no compassion for his dying brother. Dick trys to run after him but Bruce stops him telling him that this wont be the last time they will encounter Roland. After the fight, The three heroes have a talk at Grayson's apartment and they decide to become allies because Dick does not want to be the sidekick that he once was. Grayson feels that he can be a hero equal to Bruce because Dick feels that he is Bruce's equal and not his lesser. Bruce and Barbara go back to Gotham and the movie ends with Nightwing in his signature pose sitting on a gargoyle watching over Bludhaven with a monologue over the scene said by Dick saying that he is the hero this city needs and he will do everything he can to stop Desmond.
Sean Faris will return as Nightwing/Dick grayson
John Malkovich will return as Roland Desmond
Mel Gibson as Mark Desomnd/Blockbuster
Emma Stone will return as Barbara Gordon/Batgirl
Jon Hamm will return as Bruce Wayne/Batman