A dead prostitute. A detective with baggage, enemies and a charming sidekick. A twisting plot, breathless conclusion. We've been here before surely? Well no, because this is Nairobi, memories of the US Embassy bomb still fresh, in the grip of a violent election, tribal and racial rivalries erupting. Add child trafficking and female genital mutilation and things are different. Not your usual whodunit, but one I needed to get to the bottom of.