In the distant past under Bresling dynasty, Edwina Moira had the dream to build an Asylum at the site of her ancient mansion. The Baron helped bring her dream to life in in year BRy459 (year of Bresling).
Moira Asylum was originally a treatment facility for the insane and other mental ailments. Inspired in part for treating individuals such as the legendary master Sneak Thief (Garrett from the original trilogy) for their obsessive compulsive and kleptomaniac tendencies. Later under Ulysses Northcrest he saw to turning it into a prison to keep the degenerates and undesirables out of society (designing something that the Sneak Thief would not be able to escape as he had come to be seen as the cause of the Dark Age which the The City had been forced to live under).
It has since kept notable characters such as Erin, Aldous and Montonessi. It is unclear who the administrator of the facility was but Doctor Huntfield wanted to take over. When Erin was brought there after taking in the primal, she was experimented on by the Baron. Eventually Erin's presence corrupted the inmates of the prison facility which turned them into freaks. This resulted in the staff of Moira Asylum either being killed or fleeing. It appears that some of the inmates survived the freaks as they roam the treatment level of the asylum. Also, after going into Erin's room, an inmate (and now apparation) named "The Night Warden" patrols the male ward. The are four parts of the asylum in the game. The female ward, the male ward, the treatment level, and the prison level.
- Moira Asylum
- Men's Ward
- Women's Ward
- Women's Dining Hall
- Treatment Center
- Main Building
- Third Floor
- Old Prison
- Maximum Security
- The Moira Asylum is named for the owner and in the same or similar location as Overlook Mansion owned by Edwina Moira in Thief: Deadly Shadows. A statue of Edwina Moira with a dedication plaque with her full name appears in the front courtyard of the asylum. The history documents for the Asylum also speak of Widow Moira's part in creating the asylum.
- In the ward areas a woman's voice can be heard saying to bring Edwina her wine. This is once again a reference to Edwina Moira from Thief: Deadly Shadows. The ghost of Edwina Moira also appears and shuts you out of a room with ghostly fire while speaking to Garrett. Both events refer to some of the events that occur in Deadly Shadows (where Garrett is tasked to bring Edwina her wine).
- The Moira Asylum is very similar to The Shalebridge Cradle. Where the Cradle was a combination of sanitarium and orphanage. The Moira Asylum is a combination of an asylum and prison.
- The prison area is reminiscent of the Pavelock Prison in Thief: Deadly Shadows.
- In Deadly Shadows Garrett had the choice of either robbing Moira of her inheritance or letting her keep it, depending on the difficulty. On expert the mission parameters require him to steal it. This appears to be the motive behind her wanting to create a hospice to treat people like Garrett.
- The upper areas of the Asylum look to be of modern construction in the style Theodore Eastwick is noted for, possibly renovated several times over the centuries (although portions of the façade and lobby resemble sections of the old mansion at least in layout). The Old Prison underneath is built in a much older architectural style, and dates back to a few years or decades into the Asylum's founding.