Smokeheads — Doug Johnstone

Four friends, one weekend, gallons of whisky. What could go wrong?
Driven by amateur whisky-nut Adam, four late-thirties ex-university mates are heading to Islay - the remote Scottish island world famous for its single malts - with a wallet full of cash, a stash of coke and a serious thirst.
Over a weekend soaked in the finest cask strength spirit, they meet young divorcee Molly, who Adam has a soft spot for, her little sister Ash who has all sorts of problems and Molly's ex-husband Joe, a control freak who also happens to be the local police. As events spiral out of control, they are all thrown into a nightmare that gets worse at every turn.
A wild trip to the Scottish Highlands, Doug Johnstone's debut on the Faber crime list is a classic violent thriller, doused with black humour.