Guilty by Definition

Susie Dent
65 pages2-hour read
Fiction
Novel
Adult
Published in 2025

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Character List

Meet the key characters, with insights into their roles, motivations, and relationships—spoiler-free.

Major Characters

A dedicated lexicographer who recently returned to her hometown after spending a decade living in Berlin. She frequently retreats into her intellect and relies on her professional routine to process difficult emotions. She carries a heavy burden of guilt and unresolved grief over her older sister's sudden disappearance thirteen years prior, preferring the quiet order of words to chaotic personal realities.

Key Relationships

Younger Sister of Charlotte "Charlie" Thornhill

Daughter of Gabriel Thornhill

Mentee and Colleague of Alex Monroe

Colleague of Safiya "Safi" Idowu

Colleague of Simon Turner

Former Acquaintance of Jonathan Overton

Goddaughter of Gemma Waldegrave

Person of Interest to Oliver Caldwell

Former Employee of Mike Orme

A brilliant and beautiful former PhD student who vanished without a trace in 2010. She worked part-time at the CED and is remembered by some as a golden girl, while others found her arrogant and dismissive of those she considered less capable. Her fierce ambition and secretive nature left behind a complicated legacy that continues to disrupt her family.

Key Relationships

Older Sister of Martha Thornhill

Daughter of Gabriel Thornhill

Ex-girlfriend of Tom

Former Employee of Brin Edwards

Mentee of Dr. Catherine Carmichael

Former Employee of Mike Orme

A charismatic celebrity academic and consultant editor for the dictionary's Shakespeare coverage. He carefully cultivates his public image and jealously guards his status as a preeminent scholar. His effortless success and territorial attitude toward his subject matter often trigger resentment among his less famous peers at the CED.

Key Relationships

Husband of Olivia Overton

Former Acquaintance of Martha Thornhill

Rival of Simon Turner

A sharp, elegant editor at the CED who provides pragmatic wisdom to her colleagues. She observes people closely and possesses a deep interest in folklore, horror, and history. Her confident exterior hides a fiercely private personal life and a strong protective instinct toward her friends.

Key Relationships

Mentor and Colleague of Martha Thornhill

Colleague of Safiya "Safi" Idowu

Colleague of Simon Turner

Ex-wife of George

The youngest member of the lexicography team. She brings an enthusiastic energy and modern digital research skills to the office. Her passion for regional words and her meticulous note-taking habits make her an invaluable asset to her more seasoned colleagues.

Key Relationships

Colleague of Martha Thornhill

Colleague of Alex Monroe

Colleague of Simon Turner

Housemate of Josh

A highly skilled but curmudgeonly dictionary editor with a passion for etymology. He struggles with financial strain and bitterness following a difficult divorce and a stalled career. His cynicism makes him a sharp observer, though his professional envy frequently poisons his interactions with others.

Key Relationships

Colleague of Martha Thornhill

Colleague of Alex Monroe

Ex-husband of Nancy

Father of Chloe

Supporting Characters

The grief-stricken father of Martha and Charlie. He lives as a recluse in a neglected family home, fiercely preserving Charlie's bedroom as an untouched shrine. He struggles to communicate his complicated feelings to his surviving daughter and harbors deep fears regarding the past.

Key Relationships

Father of Charlotte "Charlie" Thornhill

Jonathan's wife and former student. She presents a polished, watchful exterior to the academic community. She is fiercely protective of her husband's reputation and has a history of spreading malicious rumors to guard their social standing.

Key Relationships

Acquaintance of Martha Thornhill

A powerful literary agent who represents high-profile academics. She is also a longtime friend of the Thornhill family, positioning her at the intersection of professional ambition and personal loyalty. She fiercely protects the interests of her most successful clients.

Key Relationships

Liter Agent of Jonathan Overton

Godmother of Martha Thornhill

A calm, professional police detective reviewing the cold case of Charlie's disappearance. He treats new evidence seriously and provides a grounded, official perspective that contrasts with the academic environment of the dictionary editors.

Key Relationships

Investigator for Martha Thornhill

The former head editor of the Clarendon English Dictionary. He managed the team during the turbulent period when Charlie vanished and prioritized institutional reputation over uncomfortable truths.

Key Relationships

Former Employer of Martha Thornhill

Former Employer of Charlotte "Charlie" Thornhill

Charlie's former boyfriend, whose surgical training was derailed by the stress of police scrutiny following her disappearance. He remains somewhat forgiving of the Thornhill family despite the lasting damage to his mental health.

Key Relationships

Husband of Tanya

Ex-boyfriend of Charlotte "Charlie" Thornhill

Tom's wife and a former university friend of Charlie. She holds deep resentment toward the Thornhill family for the trauma inflicted on her husband and fiercely guards their current domestic peace.

Key Relationships

Wife of Tom

Former Friend of Charlotte "Charlie" Thornhill

An antiquarian book dealer who mentored a young Charlie in the rare book trade. He carries a lasting sense of professional betrayal regarding her secretive business practices.

Key Relationships

Former Employer of Charlotte "Charlie" Thornhill

Charlie's former PhD supervisor. She provides crucial insight into her student's waning interest in official studies and her increasing distraction with a secret project.

Key Relationships

Former Academic Supervisor of Charlotte "Charlie" Thornhill

An archivist at the British Library who specializes in early modern manuscripts. He is a methodical man whose rigid routines ultimately ended his marriage.

Key Relationships

Ex-husband of Alex Monroe

Safi's housemate who keeps his ear to the ground for local university gossip. He hosts art shows and provides the team with crucial social context about prominent academics.

Key Relationships

Housemate of Safiya "Safi" Idowu

Simon's former spouse. She maintains a tense but necessary line of communication with her ex-husband due to their shared custody arrangements.

Key Relationships

Ex-wife of Simon Turner

Mother of Chloe

The infant daughter of Simon and Nancy. She serves as a tether connecting her parents despite their fractured marriage.

Key Relationships

Daughter of Simon Turner

Daughter of Nancy