Dr. Amadeus Arkham: Founder of the asylum, Amadeus named the institution after his deceased mother Elizabeth.[1]
Dr. Harleen Quinzel: A former psychiatric intern, Quinzel was seduced by the Joker and adopted the supervillain name "Harley Quinn".[8]
Dr. Jeremiah Arkham:
Nephew of Amadeus Arkham, Jeremiah was the head of the asylum in
current continuity until recently, in which he too was driven insane and
became the second Black Mask.
CO Aaron Cash: One of Arkham's most respected security guards. His hand was bitten off by Killer Croc,[9]
and he sports a prosthetic hook in its place. Unlike many of his
colleagues, Cash is neither insane nor corrupt, and is a trusted ally of
Batman.[10]
Dr. Alyce Sinner: Chosen by Jeremiah Arkham as his second in
command, and briefly committed under Arkham's orders, Sinner became head
of the asylum after Arkham was revealed as Black Mask. She is secretly a
member of Intergang's Church of Crime, working with Black Mask.
Dr. Joan Leeland: Once a colleague of Harleen Quinzel, Dr.
Leeland soon became her therapist, along with treating other known
inmates such as Jonathan Crane (Scarecrow) and Harvey Dent (Two-Face).
Warden Quincy Sharp:
Officer Frank Boles:
William North