Amanda is a determined and often ruthless true-crime author writing a book about the mysterious Alperton Angels case for a new series called "Eclipse." Driven by a compulsion to uncover facts, she employs questionable methods, including phishing calls and blackmail, to secure interviews and confidential information. Her single-minded ambition isolates her personally, though she maintains a complex, competitive dynamic with a rival author.

Oliver is a well-connected author and former public relations professional writing a competing book on the Alperton Angels. He and Amanda share a tense history from their time as trainee journalists twenty years prior. Currently grieving his father's death and dealing with mysterious early-morning phone calls, he insists he only cares about objective facts, yet exhibits signs of deep psychological vulnerability.

Born Peter Duffy, Gabriel is the enigmatic leader of the Alperton Angels, currently serving a life sentence for murder and the mutilation of his fellow cult members. Charismatic and highly persuasive, he convinced vulnerable teenagers that they were angels tasked with a divine mission. Even from inside prison, he possesses a mesmerizing voice and an unsettling ability to read people.

Ellie is Amanda’s former assistant and a current PhD student in criminology. She transcribes Amanda's interview recordings, frequently inserting her own commentary, reactions, and observations into the text. Acting as an unofficial sounding board, she provides objective analysis of the case and expresses genuine concern for Amanda's well-being and ethical choices.

Holly is one of the two vulnerable teenagers indoctrinated into the Alperton Angels cult by Gabriel Angelis. Having spent time in foster care, she was susceptible to Gabriel's narrative that she was an angel with a divine purpose to protect a baby. She survived the horrific events at the warehouse in 2003, and her current whereabouts are heavily protected by the authorities.

Jonah is a former teenage member of the Alperton Angels who survived the mass death event at the warehouse. Lacking a stable family structure, he was fully drawn into Gabriel's extreme ideology. Years later, he continues to live an isolated life, maintaining a steadfast belief in the cult's original teachings about angels and dark forces.

Don Makepeace is a retired chief inspector who first encountered Gabriel Angelis during a fraud arrest in the 1980s. He was serving at Wembley Central during the time of the Alperton Angels incident. As an ex-special forces member turned police officer, he maintains extensive contacts and shares strange anecdotes from his career.

Sonia is a social worker handling sensitive information regarding the Alperton Angels survivors. She is pressured by Amanda to track down the current identities of Holly, Jonah, and the baby. Despite Amanda's aggressive tactics, Sonia attempts to maintain professional boundaries.

Pippa is an editor at Kronos publishing who commissions Amanda to write a book for the new "Eclipse" series. Focused on marketability and fresh angles, she explicitly instructs Amanda to locate the baby who survived the Alperton Angels case.

Neil Rose is a police constable who, along with his partner, responded to Holly's emergency call at an abandoned baby food warehouse. He transported the shocked, blood-covered teenager to the hospital but failed to notice she was carrying a live baby, an oversight that led to professional discipline.

Aileen Forsyth is a police sergeant tasked with reuniting Holly and the baby with Jonah on the night of the warehouse incident. She witnessed Holly's contradictory behavior toward the infant and had to manage a highly volatile Jonah before transporting them to a children's center.

Marie Claire is a mysterious figure initially identified as a police officer who interacted with the cult survivors on the night of the mass deaths. Her presence at the hospital causes Holly to become hysterical, calling her a "dark angel."

Harpinder Singh is a young man whose murder leads to Gabriel Angelis's life sentence. Initial media reports describe him as a destitute waiter newly arrived from India, though amateur sleuths suggest his background is much more complex.

Minnie is a fellow true-crime author writing a book about Myra Hindley and Rose West for the same "Eclipse" series. She is friendly and attempts to socialize with Amanda, eventually helping her research the educational background of individuals connected to the case.

Nita is Amanda’s literary agent who secures her the contract for the Alperton Angels book. She views the true-crime genre as their primary source of income and helps navigate the demands of the publishing house.