When one of the better-known drug barons in Edinburgh, Chick Mathieson, is killed, lawyer Tam Buchanan is reluctantly drawn deep into the city's underworld. Freddie McAuslan, the young man arrested for Mathieson's murder, has recently done time for a crime that was almost certainly committed by Mathieson himself, and Buchanan is convinced of his innocence. Aided by his sleuthing partner Fizz and her grandpa, who is in Edinburgh for an operation on his famous clicking knees, he sets out to prove it.
The trail leads to Greenfield House, a sheltered housing unit for indigent show-biz geriatrics, a background which, on the surface, could not be further removed from the murky world of Edinburgh crime. In order to carry out some undercover espionage, Fizz gets Grandpa installed at the shelter for a few days' recuperation. Could any of the aged Thespians really have been involved in the death of Edinburgh's Mr Big? It's unlikely - but when Fizz gets caught up in the most terrifying experience of her life, it seems that she and Buchanan have got a little too close to the truth.
