1 / 4Guilty by Definition by Susie Dent
Guilty by Definition by Susie Dent is a linguistic mystery about a coded letter, a missing woman and the search for answers. Martha Thornhill follows word-based clues connected to the disappearance of her sister Charlie, with the story set around the Clarendon English Dictionary office and Oxford.
At a glance
- The plot centres on Martha Thornhill, whose sister Charlie disappeared ten years earlier.
- Anonymous letters bring linguistic clues and a troubling secret into the investigation.
- The publisher describes the book as a mystery about language, family and the after-effects of a disappearance.
Reference price: £9.99
Price checked: 12 Nov 2026
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Pros and cons
Pros
- A missing-person mystery incorporates word clues and an English dictionary setting.
- The 400-page length gives room for a layered investigation and family story.
Technical specifications
8 specifications| Publisher | Zaffre |
|---|---|
| Publication date | 24 April 2025 |
| Language | English |
| Print length | 400 pages |
| ISBN-10 | 1804183970 |
| ISBN-13 | 978-1804183977 |
| Weight listed | 278 g |
|---|---|
| Dimensions | 12.9 x 2.5 x 19.7 cm |
Who is it for?
Customer reviews on Amazon
- 5 stars
52% 52% - 4 stars
30% 30% - 3 stars
13% 13% - 2 stars
3% 3% - 1 star
2% 2%
Customer feedback describes the book as engaging and well written, with praise for its clever twists, strong female characters and chapter headings featuring lesser-known words and definitions. The story’s word-focused mystery gives those elements particular relevance to readers seeking language alongside suspense. Aggregate ratings are mostly four- and five-star, though a smaller share are lower, and ratings alone do not explain individual reactions.
Positive themes
- Customer feedback praises the engaging prose, clever plot twists and strong female characters.
- Readers are reported to appreciate lesser-known words and definitions used as chapter headings.
Frequently asked questions
What is Guilty by Definition about?
Martha Thornhill investigates anonymous letters containing linguistic clues that may reveal what happened to her sister Charlie, who disappeared ten years earlier.
Who wrote Guilty by Definition?
The listing identifies Susie Dent as the author.
How long is the book?
The listed print length is 400 pages.
What language is this edition?
The product details list the language as English.
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