6 months later, 15 year old Dick Grayson is now in constant radio contact with Batman to help him monitor multiple police bands and their wire tapings, being anxious to take to the field against Bruce’s protests. They have developed an anti-toxin for the pollen toxin, but are finding the neurological steroid has been amped up. More TIGER guards-and even some common thugs- are increasing in strength and brutality at the cost of their overall intelligence.
Meanwhile, Blackgate receives it’s transfer of prisoners from Arkham Asylum, with one prisoner not even being allowed on a Hannibal-like gurney; instead they simply transport a full size coffin into his new room. The mayor, in attendance with Strange, wonders why Strange even wanted “the Clown.” Strange exposits how his theory of Batman’s creator aspect is no where better personified than this inmate. He invites the Mayor, Gordon, and Bullock to observe his first interview with the Joker. Gordon alone insists on staying because he doesn’t trust Strange or the Joker.
Dick Grayson, now formally allowed as Bruce’s ward, is showing considerably better humor since his training, as is Bruce himself. It’s established that they have a sibling-like repartee, including Robin teasing Batman about always letting the new “Catwoman” get away, though Batman insists he has his reasons, with Alfred snarkily saying one of them is probably tight leather and a whip. Dick’s phone goes off and he pulls it up to see that the Batcomputer has finally located a haggard looking Zucco, and that he is under attack from TIGER guards. Bruce immediately suits up, but forbids Dick from coming along, even locking down his costume.
At Blackgate, Joker gets his one big scene in a creepy interview with Strange. Despite being apparently doped to his gills, Joker manages to play Strange like a fiddle, especially by analyzing how he wants to replace the Batman and even suggests that Strange probably imagines running around in his own suit, and parenthetically threatens Gordon’s family even though he’s behind a one way mirror. Strange gets him to relate the events of his creation, though the only consistent bit in each version that he tells is how he winds up falling into acid at Ace Chemicals apparently at the instigation of Batman. Strange cites him as a true example of Batman’s ability to create monsters. Joker asserts that he was not created; he simply is. He had one bad day and became a supervillain. He laughingly states that you never really see it coming.
We visit Poison Ivy’s hospital bed, where she allows one of the guards to kiss her so she can headbutt him. He angrily grabs her for another kiss, only for her to bite him, and he angrily injects her with an overdose of Strange’s neurological toxin. As he walks away he notices a slight feeling of wooziness…
Batman arrives to find Zucco’s hideout already destroyed. He manages to fight his way through Zucco’s few remaining henchmen before the TIGER guards manage to fight their way into the room. When Batman manages to take them out while also protecting Zucco, we see Strange reluctantly order a wide dispersion of the pollen to kill him, telling the Mayor that the vigilante has obviously shown his true colors by protecting Zucco. The Mayor objects, so Strange quietly orders one of his men to take him prisoner.
Batman almost dies in the pollen attack, but Robin arrives to inject him with the anti-toxin, and after some hesitation does the same to Zucco. Zucco, in much worse shape than Batman, passes out, but not before semi-lucidly blaming the Penguin for the Graysons’ deaths.
Back in Poison Ivy’s room, the guard is showing signs of being much worse, and he is so far gone that he doesn’t hear the other guards yelling about how out of control the plants in Ivy’s room have gotten-they can’t even reach her anymore. Suddenly, the plant starts attacking them, crushing them all in a matter of seconds. The sick guard, now almost all gone, just barely manages to raise his gone when a giant flower opens in front of him, revealing the fully transformed Poison Ivy, whose body has in conjunction with the plant retrofitted the neurovirus to bond her to her plants and mutate them into powerful and mobile monstrosities. She teasingly tells him he was poisoned by her “kiss” and finishes him off with quite a painful looking repeat. She calls him “stupid meat” and leaves to find Strange.
Gordon and the cops show up to help Batman out of the wreckage, revealing how Strange has kidnapped the Mayor and being surprised at Robin. Batman tells Robin to make sure Zucco goes to jail safely, then takes off for Penguin. He arrives to question Penguin, who somewhat nonchalantly is taking cover in his private bunker and reveals that Strange had Zucco sabotage the lines to punish Penguin (through bad publicity and setting his base crawling with cops) for failing to provide him with man power for Blackgate.
Batman’s comm. System begins buzzing with the reveal that Gordon’s men are taking heavy casualties and even being captured by TIGER guards at Blackgate, then Robin reports that a giant plant monster is attacking city hall with a weird woman shouting about how she’s going to see to it the whole city burns for destroying plants.
Robin engages Poison Ivy while Batman tries to save the cops, evacuate the prison, and get inside Strange’s stronghold. It quickly becomes clear they are both outmatched by their opponents despite their gadgets. Robin tells Batman he has an idea and manages to enrage Ivy by killing some of her plants with his anti-toxin, then gets in the Batmobile and leads an angry Ivy on a chase that leads them to Blackgate , where she realizes Strange is holed up in and immediately begins attacking it, allowing Batman to get inside and leading to a massive battle. Strange and Batman briefly engage with Strange getting his butt kicked but managing to have his monstrous TIGER guards overpower Batman, and takes off Batman’s mask.
Distracted by all the implications of who and what Batman being Bruce Wayne means for his enemy, an ecstatically fascinated Strange ends up being pulled away by Poison Ivy’s plants, and she feeds him to one of her plants, though we can still see him struggling through the plant’s sides. When she turns her attention back to Batman, she seductively approaches him with a Cheshire grin, clearly setting him up to be killed by her kiss while he quietly taps something on his gauntlet computer to Robin, who opens up a valve while closing another, so that when she “cutely” asks him what he’s doing he tells her to smell the air. She screams when she realizes its gas, and Batman lights a match, setting the whole place ablaze. While she tries to finish him off with her burning plants, Robin shows up , and they manage to double team her enough for Batman to reach her and knock her out. Batman and Robin emerge from the inferno, carrying Ivy out wrapped in Batman’s cape to protect her from the flames.
Our last scene shows Batman and Robin talking to Gordon atop the police station about how Strange’s body wasn’t found-and neither was the Joker, though his cell was melted around him, so there might not actually be a body to find. They prepare for a night out, with Robin catching a glimpse of, and being seen by, Barbara Gordon. When Gordon tells Robin to dream on and Batman chastises him for being distracted on the job, Robin says his girlfriend is calling when a report comes over their comms that Catwoman has been spotted making off with Cobblepott’s money.
We end on a short scene showing them chasing her down while she says “This should be fun!”