In the opening scenes, the protagonists are sentenced to hours of community service. During his first community service session Robbie (Paul Brannigan), under the guidance of Harry (John Henshaw), is interrupted and taken to the hospital by Harry as his girlfriend, Leonie (Siobhan Reilly), has gone into labour. At the hospital Robbie is assaulted by two of his girlfriend's uncles. Harry takes Robbie back to his house, where Leonie calls to tell Robbie that his son, Luke, has been born. Harry insists that he and Robbie celebrate, and brings out a vintage whisky.
Harry takes the group to a distillery as a reward for their good behaviour, where they learn what "the angels' share" is. Afterwards, the tour guide gives them each a dram of whisky and asks them to smell it, and Robbie is complimented on his ability to identify flavours. At the next community service session, Harry approaches Robbie and asks if he'd like to come to a whisky tasting session in Edinburgh. Robbie, in turn, invites the other members of the group, where they learn about a cask of priceless whisky, the "Malt Mill", set to go on auction soon, and Robbie is passed a card by a whisky collector, Thaddeus (Roger Allam).
After they leave, Mo (Jasmin Riggins) reveals she spotted and stole documents detailing the warehouse in which the "Malt Mill" is kept. Robbie agrees to meet with a victim of his former violent crimes, Anthony (Roderick Cowie) recollects the attack. After realising that he can't continue living under threat of assault on himself and his family, he begins planning to steal the Malt Mill, with his community service partners. They secure an invitation to the tasting and auction during which Robbie hides in the warehouse overnight and covertly witnesses Thaddeus attempting to bribe Angus Dobie (David Goodall) into selling him some of the whisky before the cask goes on auction. Dobie refuses and the two leave, after which Robbie siphons some whisky from the cask into empty Irn Bru bottles and then tops it up with cheaper whisky from an adjacent cask. At the auction, the group see Thaddeus outbid by an American, who tastes the cask, and is apparently happy with the slightly diluted blend.
Afterwards, Robbie approaches Thaddeus and negotiates a sale of three bottles for £250,000. They plan to make the exchange in Glasgow, and so begin the trek home, but inadvertently break two of their four bottles during an encounter with the police. Robbie gets furious, but goes ahead with meeting Thaddeus, and negotiates a sale for £100,000 and a permanent job far away from Glasgow. Robbie reveals to his friends, that he didn't sell two bottles, but one. The scene cuts to show Harry coming home to find a bottle of Irn Bru sitting on his kitchen table next to an open window, with a note thanking him and presenting his "angels' share" next to a newspaper piece showing a photo of the payback group next to the cask. He smells the bottle and rejoices at the Malt Mill inside.
In the final scene, we see Robbie and Leonie leave for Stirling in an immaculate old Volkswagen Type 2, having made temporary goodbyes to the rest of the group. After they leave, the rest of the group resolve to go get wasted. The film ends with The Proclaimers' "500 Miles" playing.
Source: Wikipedia
