It's Damian Wayne's birthday, and the Bat-Family throws him a surprise party in the Batcave! But it seems someone has other plans, as a pair of ancient Hittite deities crash the party! Robin's battle with Tarhun and Arinitti takes him on a wild ride all the way to Budapest, ultimately leading him to his grandfather, Ra's al Ghul. As Batman wages a battle to rescue his son, Damian is left to ponder a life-altering question: choose immortality and stand at his grandfather's side, or choose mortality and continue on his path alongside his father.