Gorillas in our Midst!

Teaser: Professor Milo designs a way to control rats, and uses his new technology to steal diamonds only to run afoul of Batman and the Spectre.
Main Plot: When Gorilla Grodd, Monsieur Mallah, and Gorilla Boss form G.A.S.P. (short for Gorillas and Apes Seizing Power) and replace all of Gotham City’s entire human population with gorillas, Batman teams with Detective Chimp, B’wana Beast, and Vixen (after the latter two stop Killer Moth and his henchmen from robbing an armored car) to thwart Gorilla Grodd’s plans.