This from Marcel Berlins’ crime round-up:

The Dead Can Wait by Robert Ryan
Dr John Watson was not, it seems, quite as dim as he’s portrayed in the Sherlock Holmes stories. Robert Ryan (with the consent of the Conan Doyle estate) reveals his true mettle. The Dead Can Wait is in no sense a pastiche, but a seriously good, very readable, well-researched novel incorporating the First World War, detection and espionage. It is 1916. Watson has become an expert on the injuries and mental traumas suffered by soldiers in battle. The British are secretly developing a new kind of weapon. But, in its first test, seven men involved become insane, then die spectacularly. The sole survivor is rendered mute. Watson is commanded to discover the causes of the tragedy, but there are foreign spies around and enemies within.
The Dead Can Wait by Robert Ryan, Simon and Schuster, 463 pp, £18.99. To buy this book for £14.99, visit thetimes.co.uk/bookshop or call 0845 2712134

The novel is partly set on ‘the most lethal road in England’, of which more later: