During a leisurely softball game at Gotham State penitentiary, Jervis Tetch, the sinister Mad Hatter, steals home and keeps right on going, along with the cap of Warden Crichton (who was umpire). Later, he and his henchmen swipe 700 hatboxes from BonBon's Boutique (after Mad Hatter gives its namesake proprietress a taste of his Super Mesmerizer in his top hat), and he and his moll, Polly, use the hatboxes to put his entire collection of heisted headgear into storage. Jervis then tells Polly that he has lost all fascination with stealing hats and announces he is altering his tactics to instead use hats for crimes! Alerted to the hatbox heist, Batman and Robin use The Batcomputer to predict The Mad Hatter's next criminal scheme, which is the robbery of Hattie Hatfield's ruby from The Headdress Ball at The Top Hat Room.

Jervis Tetch, in cognito as The Three-Tailed Pasha Of Panchagorum, of course, removes the ruby just as The Dynamic Duo arrive and he quickly throws his gimmicked fez to the floor, which causes an explosion of fireworks. In the confusion, The Hatter manages to spritz The Batman's cowl with radioactive spray (turning it bright pink!) before he and his men make a break for it. The Caped Crusader, who strategically ingested an Antiradioactive Batpill beforehand, and The Boy Wonder rushes to Professor Overbeck at The Atomic Energy Laboratory, where Tetch, in disguise as Overbeck's assistant Otto Puffendorfer, snatches the pink cowl just as The Batman changes into a spare one. The Dynamic Duo leap out to confront Jervis The Hatter and his crooked cohorts only to be immediately overtaken, captured, and trapped inside a gigantic X-Ray Accelerator Tube and Fluoroscopic Cabinet, which when activated will permanently irradiate The Duo!