|“||I know, it sounds strange. But what I did was very important. I helped him smite an evil man. I was chosen. For redemption.||”|
— Gloria Sidnick to Sam Winchester
Gloria presumably worked as a prostitute, and one night while chain smoking and watching television, the man on television begins preaching about angels sending messages that needed to be heard.
At the same time, the signs the man speaks of begin occurring in Gloria's home. The lights flicker and the room shakes, and while Gloria sits on the couch, frightened, a bright light shines behind her and she turns round, awe-struck, and utters, "Oh my god".
This mysterious entity commands Gloria to commit murder, by stabbing a man in the heart. Gloria obeys, and is subsequently put in a mental hospital, with people declaring her insane or crazy. Sam Winchester visits her shortly after to discuss her case. Gloria is convinced God sent a message through an angel, and believes the man she killed had committed a heinous sin. As it turns out, this man - Carl Gully - was a serial killer. Gloria is also the second person to commit murder and claim it was ordered by an angel.
Later on, it is revealed that what spoke to Gloria wasn't an angel, but the spirit of Thomas Gregory.