HRF Keating was a grand old figure in British crime writing of the later 20th century, in large part due to the success of the series inaugurated by this book. The setting is Mumbai; the protagonist is Inspector Ghote, who will go on to feature in 25 books or so, along with the odd film (notable that this is the first in this CWA series to feature a serial detective, though there's more to come).
Now, look, Keating is held in great affection by many, and no doubt Ghote is too, so perhaps the kindest thing to say is just that this book now feels very dated, without pursuing post-colonial critique too fiercely. I mean, and I wasn't in Mumbai in the 1960s, and for all I know it could be that every cliché of urban India was in fact true of the time and the place. And for all I know every Indian did speak some more or less schooled variant of the mannered English on the lips of all the characters.
I say "on the lips". We also get a fair amount of this stuff when the free indirect authorial voice comes close to the Inspector's thoughts. When the voice is distant, it often adopts a sort of light-comic Wodehouse tone that seems to have been almost a default mode for crime writing around this time. I suppose a lot of people like it, but it sets my teeth on edge, and I'm glad we now have a sub-category for the kind of stuff likely to be written in this style ("cosy crime") so that I can safely ignore it.
Behind the Indian hokum and the bantering nonsense about traffic, there's a fairly decent formal structure to this story. A pretty classic locked-house deal: small circle of suspects, all with prima facie motive for the central crime (assault that might become murder). It ticks along OK without really getting going; I realised three quarters of the way through that, although I had been told that the suspects all had motives, I couldn't really grasp what they actually were. The twist at the end is predicated on your having paid a bit more attention than I did.
Overall: OK, but I'm not going to rush to read the other 24.