Maggie first saw Brenda during her attempt to talk to Lucy, who was still angry at Maggie for kissing Lucy's then-boyfriend, Parker (the reason for her ex-communication). She informed Mel about Brenda's appearance and voiced her bewilderment over her being in with the Kappas so quickly. An online search for Brenda revealed that she actually died in 1989 when she fell off a roof while drunk on wine coolers, revealing that Brenda is a ghost.
Mel and Maggie cast a spell that sent them back to the late 1980s, and witnessed Brenda being humiliated by her former friend, Jenna Gordonson, who was Kappa president at the time. This led the pair to believe that Brenda was a banshee, as they figured that Brenda's death was caused by sorrow. After the sisters and Harry Greenwood saved a group of Kappas, Mel and Maggie visited Jenna at her home and asked about Brenda. Jenna revealed two things: that Brenda's death was the first of a long list of Kappa deaths that had been occurring, and that Brenda wasn't the victim of Jenna's bullying: she was the bully. Brenda was revealed as manipulative and backstabbing (she slept with two of her sorority sisters' boyfriends), and on the day of her death, she was lashing out at the entire sorority while drunk.
Mel and Maggie corrected their original conclusion and came to a different one: Brenda was actually a Revenant, a vengeful and angry spirit. She had been haunting the Kappa house for years and killed many of the girls, doing so in the same fashion--manipulating them into getting drunk and then coercing them to jump off the roof. The ghostly villainess appeared to Lucy while she was meditating and used her anger at Maggie to attempt to add her to her list of victims, and just as Mel, Maggie, and Harry arrived, the evil Brenda began her attempt to kill Lucy, stating to her that she should jump to her death to hurt Maggie. Lucy dove from the roof, only to be saved by Harry, but it was afterwards that Brenda coerced Lucy to kill Maggie. During Lucy's attack, Maggie stated to her former friend that she knew that she hurt her by kissing Parker and should have realized that she needed space. Lucy confirmed Maggie's heartfelt statements, and that caused Brenda's evil spirit to be destroyed.