When polite arguments between members of an exclusive wine tasting society take on a sinister turn, private detective John Tedesco and wine merchant Jos Elsted find themselves caught up in the fallout. Can they work out how and why an outwardly respectable group of wine experts have turned into murder suspects? As his investigations lead him to the island of Madeira , Tedesco encounters a fellow private detective, Tony Camacho, and an opinionated former royal correspondent called Sir Reggie Challenor, who provide him with some interesting leads. Meanwhile , back in Rhyminster, Jos helps the police as they investigate the backgrounds of the club members, which reveals some real surprises. Can Tedesco and his team, including Barker the border terrier, crack the case before the final tasting?