Who Susan Ryeland is
Susan Ryeland is a London book editor whose professional life becomes entangled with the detective novels she edits. She understands how a story is built: which details an author has chosen, what has been left out, and when a seemingly straightforward explanation fails to make sense. Those everyday editorial habits become her tools as an amateur investigator.
Susan is an unusually practical heroine for such elaborate mysteries. She has a job, a relationship and a sister who can puncture her confidence. Her curiosity is neither a police assignment nor a hobby comfortably fitted around everything else. Following a manuscript’s unanswered questions costs her time and creates friction with people who would prefer her to stop reading quite so closely.
Role in the three mysteries
In Magpie Murders, Susan works at Clover Books, where Alan Conway’s successful Atticus Pünd novels are important to the business. His latest manuscript arrives without its solution. Searching for the missing ending takes her out of the office and into the author’s life, where the people who inspired his characters have their own accounts of him.
Moonflower Murders begins with Susan running a hotel in Crete with Andreas. Lawrence and Pauline Treherne ask her to investigate their daughter Cecily’s disappearance. Cecily had read Atticus Pünd Takes the Case and believed it explained an old murder at their hotel, Branlow Hall. Susan must return to a book she once edited and notice things she missed when it was merely a publishing project.
In Marble Hall Murders, Susan is back in London, editing a continuation of the Pünd series by Eliot Crace. A new author means a new set of grievances behind the fiction. The assignment asks whether she can protect the detective’s familiar voice while recognising what Eliot is using that voice to say about his own family.
Key relationships
Atticus Pünd is both the detective in the books and Susan’s imagined conversation partner. Their exchanges make reading an active process: she can challenge his reasoning, and he can expose weaknesses in hers. Andreas Patakis offers the possibility of a life beyond publishing, while Katie Williams connects her to family history that cannot be put aside as neatly as a finished manuscript.
Her relationships with Alan Conway and Charles Clover begin professionally, but neither remains safely contained within work. Susan knows what their public roles require them to say. Investigating means learning how much those familiar roles conceal.
Played by Lesley Manville
Lesley Manville plays Susan Ryeland. Her performance moves between dry editorial scepticism and the vulnerability of someone discovering that people close to her have controlled the story she believed.
Their story and fate — spoilers
Susan discovers that Charles murdered Alan to prevent him exposing the humiliating secret encoded in the Pünd books. Charles also tries to kill Susan in a fire at Clover Books; she survives. Her departure for Crete is therefore a response to a destroyed professional world as well as a romantic decision.
In Moonflower, she exposes Aiden MacNeil as the killer of Frank Parris and Cecily. Her reading helps unravel the case against Stefan Leonida. The success is bitter: she can explain Cecily’s disappearance but cannot bring her back. The story gives Susan a satisfying solution without allowing detection to erase the damage that made the investigation necessary.
Marble Hall ends with Susan establishing her own imprint, Redlayn Books. Blakeney completes Pünd’s Last Case, and she plans to publish his first original novel. Katie’s partner David helps raise the funds for the business. Susan also promises Pünd that his own study of crime and detection can reach readers, giving their imagined partnership a future beyond the three investigations.
Books and television — book spoilers
The television adaptation brings Susan and Pünd into conversation, a visual and dramatic expression of her relationship with the books. It also intercuts the contemporary and manuscript investigations. The novels can let the reader inhabit a long section of Conway’s fiction before returning to Susan; television repeatedly sets the two worlds beside one another.
Anthony Horowitz also expanded Susan’s family story for Magpie’s adaptation. Her father and the painful history surrounding her mother give the television Susan an emotional connection to the manuscript’s broken families. This is more than additional backstory: it makes Conway’s habit of borrowing other people’s lives feel like an intrusion into hers.
Read or listen to the book
Magpie Murders (2016)
Anthony Horowitz’s novel behind the first television mystery.
Waterstones · print Audible · audiobookMoonflower Murders (2020)
Anthony Horowitz’s novel behind the second television mystery.
Waterstones · print Audible · audiobookMarble Hall Murders (2025)
Anthony Horowitz’s novel behind the third television mystery.
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