Comic Title: Detective Comics #91
Publisher: DC (Detective Comics, Inc.)
Address: 480 Lexington Avenue, New York, NY
Cover Date: September 1944
Approx. On Sale Date: July 21, 1944 Copyright Date July 18, 1944
Source: Library of Congress, Periodicals 1944
Until 1958 DC did not report actual on sale dates to the copyright office
The publication dates listed in LoC records are NOT release dates.

Frequency: Monthly
Cover Price: $0.10
Page Count: 48
Editor: Jack Schiff

Title: "The Case of the Practical Joker"
Pages: 13

Feature(s):
Batman (of Earth-2)

Writer: Edmond Hamilton
Artist: Dick Sprang

Reprinted In:
Batman Archives Vol. 4 HC (1998)
Batman:The Golden Age Omnibus Vol. 3 HC (2017)
Batman:The Golden Age Vol. 6 TPB (2020)

Feature Character(s)

• Batman (last appearance in Detective Comics #90; next appearance in World's Finest Comics #15)

Supporting Character(s)

• Robin (last appearance in Detective Comics #90; next appearance in World's Finest Comics #15)
• Commissioner Gordon (last appearance in Batman #24; next appearance in World's Finest Comics #15)

Villain(s)

• Joker (last appearance in Batman #23; next appearance in Batman #25)
• Joker's gang (no further appearances)

Other Character(s)

• Several prison guards and prisoners (no further appearances)

Synopsis:
The Joker is the victim of practical jokes in prison. Batman disguises himself as a guard to learn the reason behind the jokes. He soon learns that the Joker played the pranks on himself in order to cover an escape plan. Despite Batman’s efforts the Joker is successful in escaping jail.

Joker then begins a string of robberies around Gotham City. Batman remembers the Joker’s words from prison and deduces the targets of the crimes. Joker tries to escape again, but Batman has planned ahead, and the Clown Prince of Crime apprehended by the police.