Since Cadfael came out of the cloister, historical sleuthing has hit the jackpot. Go back as far as ancient Rome and you have Lindsey Davis's low-born conman Falco putting to rights the less savoury aspects of empire-building.
Move forward a millennium or so and we have Cadfael's West Country contemporaries Sir Baldwin Furnshill and Bailiff Simon Puttock chasing the rapists and making sure the murderers are hanged at the crossroads.
Step up another 300 years to the days of Good Queen Bess and her henchmen Drake and Raleigh - although Judith Cook prefers to spell it Ralegh - and you could almost say the art of accurate detection has hit the age of chemical analysis.
Cook's answer to Sherlock Holmes in School of the Night is a certain Dr Simon Forman, a gentleman of the medical persuasion who knows rather more than he should about herbal remedies. Take Eringo - or candied sea holly - for instance. According to period data - and incidentally Dr Forman really did exist - Eringo is dynamite for 'men of middle years or older'.
A sort of Elizabethan Viagra, you might say. Unfortunately some of Dr Forman's potions have rather disastrous side effects. Take too much, or doctor the dose, and you end up dead - a catastrophe that actually happened after Dr Forman is invited to the country estate of Sir Walter Ralegh for a meeting of the sinister School of the Night.
Arriving with a bag of demonstration samples, there are plenty of fellow guests eager to welcome the doctor and try the sea holly.
Like the flighty young …