Samantha and her twin brother Dane were from Atlanta. Eventually, they attended the Scholomance and became Centurions. The twins met and befriended Zara Dearborn, sharing her views on Downworlders and the Cold Peace. They soon became part of Zara's inner circle and became members of The Cohort. Samantha often bore false witness to Zara's claims of heroism, signing off on many reports that depicted Zara as an amazing Shadowhunter.
In 2012, Samantha and her brother were dispatched to the Los Angeles Institute as part of a team of Centurions sent to search for Malcolm Fade's body and the Black Volume of the Dead. Samantha was tasked with running interference with Diego Rosales and Cristina Rosales for Zara, who didn't want Cristina "stealing" her fiancé. Samantha offended the Blackthorn family when she spoke with disgust about Magnus Bane and Alec Lightwood's relationship, and insulted their brother Mark Blackthorn by calling him a half-breed.
Samantha later attended the Council meeting where Annabel Blackthorn was to testify and contributed to Annabel losing her faculties by shouting insults at her, along with the rest of the Cohort. Their leader Horace Dearborn was soon placed into power as Inquisitor after the meeting.
She soon returned with some others to the Scholomance. When Zara found out about Kieran, a faerie prince, hiding in Diego's room, they tortured him and took him to the Hollow Place. When Diego, Divya, and Rayan arrived to help him, Samantha accidentally slipped and fell into the pool. With its enchantments, Samantha saw and felt all the pain and suffering she'd caused others before she was helped out of the water by Kieran himself.
Samantha continuously screamed in agony immediately after and never seemed to truly recover, as she had been driven mad. She was brought back to Alicante and was presented to members of the Clave by Dearborn as proof against faeries at a meeting. Dearborn asked her about Kieran, and Samantha, remembering the pain she'd caused him, begged to not be asked about him nor to be seen by Diego, Divya, and Rayan. Manuel restrained her, while disguising it as a hug, through the rest of her presence at the meeting.
Samantha was an ignorant, mean-spirited girl. She showed great disdain for Downworlders and Shadowhunter "tainted" with Downworlder blood or relationships. She was quick to insult the subjects of her disdain but became upset when they fight back, as seen when she snapped at the Blackthorns not to make her feel bad after she insulted Mark and his siblings responded angrily.
Samantha, like her brother, had a thin, whippety face with pale skin and straight black hair.