 | This article needs an improved plot summary. (April 2024) |
 First edition | |
| Author | Ngaio Marsh |
|---|---|
| Language | English |
| Series | Roderick Alleyn |
| Genre | Detective fiction, Theatre-fiction |
| Publisher | Collins Crime Club |
Publication date | 1982 |
| Preceded by | Photo Finish |
Light Thickens is a detective novel by Ngaio Marsh; it is the thirty-second, and final, novel to feature Roderick Alleyn, and was first published in 1982.[1] The plot concerns the murder of the lead actor in a production of Macbeth in London, and the novel takes its title from a line in the play.