- "Oh cut the crap, will you? Once you're out it will be out of sight, out of mind. Go throw yourself off a cliff."
- —Mrs. Brimsley to her husband Mace
Mrs. Brimsley and her husband lives in a posh house, hosting a number of parties, and have sufficient money. There are rumors among the aristocracy that she worships the Outsider, through methods such as she bathed in her nephew's blood. Once Lydia Brooklaine secretly observed a party at the Brimsley household, and described the experience as "very strange".
Mrs. Brimsley along with her husband got infected with the plague and ended up in the Flooded District. She and Mace Brimsley were transported to the district. She was later arguing with her husband who still found her quite annoying.
In low chaos Mrs. Brimsley can be found with her husband as part of the Creating a Safe Haven side objective, wherein Corvo can help a group of plague survivors led by Blake escape death at the hands of the City Watch.
In high chaos she is found as a weeper along with Mace, like all the other members of Blake's group.
- A guest named Ella at the Boyle Mansion reveals some "details" about Mrs. Brimsley performing strange rituals and she worships the Outsider.
- She mentions to Corvo that she will burn Flooded District to the ground.
- When Corvo walks near her she will tell him to keep a distance from her.
- She tells Corvo that she is a Brimsley if she were at home she would throw him out.
- She will thank Corvo for helping them but will say to him "But don't expect a pat on the head!".