After Chief O'Hara inexplicably disappears one morning, thieves ransack a bank van whose route only he was entrusted with. Though Commissioner Gordon suspects the worst, Batman concludes otherwise upon finding traces of sand on the Commissioner's desk - a telltale sign of the Sandman. Then, visiting the Museum of Science with her father, Barbara Gordon becomes suspicious upon glimpsing the exhibit designer for the museum's latest acquisition, the priceless Tiger Topaz. After hours, she returns to the museum as Batgirl, and finds her suspicions correct: the designer was really a disguised Catwoman.
