Origin
Marvin and Benny used to work as guards at Arkham Asylum but they were fired for letting the Joker escape. They later worked for Sandor Cleeve and helped catch the Joker and saving the day.
Creation
Marvin was created by Dennis O’Neil for his run on The Joker.
Major Story Arcs
The Sad Saga of Willie the Weeper
For more information see: The Joker #2 – The Sad Saga Of Willie The Weeper
Marvin and Benny are fired from Arkham Asylum when they let the Joker escape, but later the pair see the Joker and Willie the Weeper, but they are blasted in the face with onion gas and the Joker gets away.
Later the pair get a job working for Sandor Cleeve, but before their first day, Benny spots the Joker and send Marvin to find the police. Marvin finds an officer, but when gets back, he finds the Joker tied up and Benny missing. Little did Marvin know the Joker had gotten the better of Benny, tied him up and dressed him to look like the villain.
Marvin does notice a man walking like the real Joker and follows him. He then gets the police and takes to the Joker and with Benny saves the day.