This slim murder mystery comes with a heavy dose of mathematical theory. Its hero is an Argentinian mathematician on a scholarship to Oxford. When his landlady is murdered he becomes embroiled in a murder investigation. A note delivered to enigmatic logician Arthur Seldom had a symbol drawn on it - a circle - and identified the murder as "the first of the series". Seldom and the narrator work together to try to solve the mystery, which they are convinced has a mathematical element.
What follows is an amiable puzzle which takes frequent diversions into short stories about murder, maths and even magic - all of which point subtly to the ultimate solution to the mystery.
At 197 pages the book is, if anything, too short. The characters feel underdeveloped and almost all would have benefited from more time on the page. Also, the short diversions throughout the book make the whole work seem choppy and unfocused in a way that they wouldn't in a longer novel.
Still, Martinez explains his maths in a relatively comprehensible fashion and does a good job of sowing red herrings throughout the book. Add to that some amusing observations about English life and a satisfying ending and you have a enjoyable and quick read.