Robin is already dead in 'Batman vs Superman', reveals Affleck

Ben Affleck, who plays a world-weary, disillusioned superhero in "In Batman v Superman: Dawn of Justice", has revealed that his trusted sidekick Robin is dead and is being mourned by the Caped Crusador at the beginning of the movie.
Batman is "bitterly disappointed... That he's lost this guy who fought by his side. That character's death must have been devastating to him, and he's suffered. We get the sense that he's suffered a lot of devastating losses before this movie even starts," Affleck told the Entertainment Weekly.
The 43-year-old's character faces of with Superman in the Zack Snider's sequel to "Man of Steel" with the trailer promissing "the greatest gladiator match in the history of the world."

Picking up Batman's story after the loss of Robin was inspired by Frank Miller's 1986 graphic novel miniseries, "The Dark Night Returns", which Snyder has said would be a key influence in his follow-up to 2013's Man of Steel.