Detective Comics (1937-) #837

A special issue featuring two of Gotham's recently reformed rogues: Harley Quinn and the Riddler! When a rogue Wayne Enterprises employee steals metahuman serum, it's up to Harley and the Riddler to crack the case!

Written By:
Paul Dini
Don Kramer
Wayne Faucher
Cover By:
Simone Bianchi