This is a enjoyable procedural with a classic age murder mystery at its heart, brought up to date with a modern London setting.  There are plenty of red herrings to keep the reader guessing, a fairly convoluted plot and some engaging sleuths.  If you like a good plotty detective novel then this ought to suit, a no-frills tale that doesn’t need any gimmicks to make it worth reading.  You could liken this to a plain ham sandwich, but one made with very good ham.  More, please.