I loved the first two Fiona Griffiths books, so was eager to read this one. I wasn't disappointed. I love it when a seemingly-banal crime turns into something far more exciting, as is the case here: a few tax fiddles in an accounts department turns into a series of murders, with Fiona going undercover as cleaner and clerk. The chemistry between Fiona and her quarry is well-handled, and the plot is resolved to everyone's satisfaction - with one exception (but I won't give that away here!)
The description of Fiona's undercover life makes this as much an espionage thriller as a murder mystery. Bingham keeps you turning the page at speed. However, he doesn't skate over the conflicts Fiona feels as she lives a double (or is it a triple?) life, and the problems she encounters trying to re-integrate.
The only weakness with this series is her father's role in events - it seems too convenient that he is a big noise in that half-hidden Cardiff that's not quite criminal but not quite legal either. Would a cop really be accepted for undercover work if her father's background was that dodgy, with all the conflicts of loyalty that might present?
No matter, this is a great book - although I'd suggest starting with the first in the series rather than starting with this one, to appreciate Fiona's back story, the better to appreciate how she's struggled to get a toe-hold on Planet Normal.