Harley Quinn, the Joker's girlfriend and former psychiatrist, has a plan to get revenge on Batman and Robin by using Poison Ivy's semi-sentient and carnivorous plants--but nothing ever seems to go right for Harley.
Clayface is pilfering untested prototype weapons and it is up to Batman and Robin to track the criminal's slime spree through the streets of Gotham City.
The Riddler has escaped from prison, and it is up to Batman and Robin to decipher the riddle he has given them, discover his plans, and prevent him from carrying out his destructive plan.