When one of the better known drug barons in Edinburgh, Chick Mathieson, is killed, lawyer Tam Buchanan finds himself wading through the dodgy dealings of the underworld. Freddie McAuslan, the young man arrested for Mathieson's murder, is an ex-client of Buchanan's father, and has recently done time for a crime that was almost certainly committed by Mathieson. Both Buchanan and his father are convinced of Freddie's innocence and set out to prove it aided by Fizz and her grandpa, who is in Edinburgh for an operation on his famous clicking knees. The trail leads to a sheltered housing unit for indigent show-biz geriatrics, run originally by the Comedy Club, a background which, on the surface, could not be further removed from the murky world of Edinburgh crime...