Superheroes Batman (Bruce Wayne) and Robin (Jason Todd) prepare to conduct a bust of a child-sexual-abuse ring in cooperation with the Gotham City Police. Unwilling to wait any longer for the police to arrive, Robin enters the warehouse and attacks the criminals against Batman’s orders. As Batman leaps in to assist his partner, he reflects that Robin has been impulsive and moody lately, which may put him in harm’s way someday. After the battle, Batman confronts Robin, trying to moderate his temper since Jason is still young. Robin explains that they had an advantage over the eight criminals in the warehouse, making police backup unnecessary. He refuses to take Batman’s warnings seriously, sardonically remarking, “All life’s a game” (11).

Several hours later, Batman returns to Wayne Manor alone and finds that Jason is still out. Still partly in costume, Bruce debriefs with Alfred and shares his concerns about Jason. Alfred reveals that he has seen Jason crying over pictures of his parents, though he refuses to talk about them when Alfred asks. Bruce and Alfred agree that Bruce may have rushed Jason into being Robin before he could work through his grief. Bruce resolves to take Jason off duty as Robin. Jason reveals that he has been eavesdropping on their conversation and gets upset with Bruce, refusing to talk again about his parents.

A newspaper reports that the Joker, Batman’s nemesis, has escaped from Arkham Asylum once again. Commissioner James Gordon explains to Batman that the Joker used janitorial chemicals to create his signature laughing gas, which killed eight guards and allowed him to escape. Batman is confident that the Joker will be caught soon since both the police and the superhero community are still reeling from the Joker’s assault on Gordon’s daughter, Barbara, which caused her paraplegia.

Meanwhile, the Joker visits a warehouse with his henchman Rupert and tells him that they’re getting ready to go on a working vacation. With most of his assets seized by the police, the Joker turns to the one hidden asset he has left: a cruise missile hidden in the warehouse. The Joker plans to sell the missile to terrorist groups in the Middle East. He quips that crime is no longer working for him and that he should pivot to international politics.

Jason goes walking for several hours. Bruce’s caption predicts that Jason will end up in his home neighborhood, Crime Alley. When he passes his old apartment building, Jason reminisces about his parents, Willis and Catherine Todd. Catherine died of an illness when Jason was still young. Willis became a low-level criminal working for the villain Two-Face, who eventually killed him. Bruce adopted Jason after he was orphaned and began training him as the second Robin immediately. Back in the present, a neighborhood woman catches Jason’s attention. He recognizes her as Mrs. Walker, Catherine’s old friend. Mrs. Walker informs him that she held on to his parents’ belongings in case he ever returned. Jason is pleased to receive them.

Batman confronts another one of the Joker’s henchmen, Gaspar Taylor, at the hotel that he’s known to frequent. Gaspar is in the middle of packing his luggage when Batman attacks. He knocks Gaspar out and goes through his things. He finds a passport and visa giving Gaspar entry to Lebanon. Batman continues his investigation across the city and finds that the Joker’s other henchmen have vacated their hideouts, leading him to infer that they have gone to Lebanon as well.

That night, Jason locks himself in his room and goes through his family’s belongings. He looks at pictures and old files and stumbles upon his birth certificate, which reveals that his birth mother wasn’t Catherine but a woman whose blotted name begins with the letter “S.” Believing that his birth mother may still be alive, Jason investigates his father’s address book and finds three women whose names begin with “S.” He uses the Batcave computer to locate the three women: Sharmin Rosen, who lives in Israel and works in the secret service; Shiva Woosan, a mercenary in Lebanon; and Dr. Sheila Haywood, a humanitarian worker in Ethiopia. Rather than asking Bruce for help, Jason resolves to visit each woman and find out which one is his birth mother. 

The Joker hijacks a military plane to ship his cruise missile overseas to Lebanon. Meanwhile, Jason uses Bruce’s credit card to book a first-class ticket to Israel. Finally, Batman discovers the Joker’s secret warehouse and deduces that he’s in possession of a nuclear weapon. He realizes the Joker’s plan to traffic the weapon and sell it in the Middle East. Batman resolves to chase the Joker to the region and stop him from completing the sale. When he reaches the Batcave, Alfred informs him that Jason has left a note expressing his intent to run away. Batman finds himself faced with a choice: either fulfill his responsibility as Jason’s guardian and go looking for him or fulfill his responsibility as Batman and pursue the Joker. Batman makes his decision but wonders if he can live with it.