Issue: #261
Last valuation update: 2025-09-26
The first appearance of Doctor Double X, this story was later reprinted in The Batman Family #7 - 13 Points To A Dead End!.
First appearances: Doctor Double X
Creators: Sheldon Moldoff, Whitney Ellsworth, Curt Swan, Ruben Moreira, Stan Kaye, Dave Wood, Charles Paris, Jack Miller, Joe Certa, Jack Schiff
Characters: Batman, Dick Grayson, James Gordon, Martian Manhunter, Karen Duncan, Captain Harding, Roy Raymond, Doctor Double X