A review by kjcharles
Bats in the Belfry by E.C.R. Lorac

Ingenious murder mystery with lots of red herrings. The style is fast and light and it's got great London atmosphere but overall rather suffered from the author explaining the plot (the policeman spends a lot of time reiterating the possible solutions). It also has a couple of nasty 30s attitudes inc a random bit of antisemitism on the part of a character so I wouldn't rush to it.