Their mission is simple: Find a cure. Stop the virus. Save the world. When a global pandemic wipes out eighty percent of the planet's population, the crew of a lone naval destroyer must find a way to pull humanity from the brink of extinction.

The series is set during Bruce Wayne's early years as the Batman, following his initial period of battling organized crime. Over the course of the season, he hones his skills with the assistance of his butler, Alfred Pennyworth. Bruce is introduced to Alfred's goddaughter, Tatsu Yamashiro. Tatsu is a martial arts swordsmaster hired to act as Bruce's bodyguard, but also recruited to act as a superhero partner to Batman.

The crew of the ship Serenity try to evade an assassin sent to recapture telepath River.