The expression was initially launched in travel retail in 2010, but it is now available exclusively at Selfridges until the end of December, when it will be rolled out across luxury off-trade outlets.
The blend includes 25-year-old Grantís single malt, the first ever laid down at Grantís Girvan distillery, mixed with 24 different malts from across Scotland.
Many come from distillers that stopped making whisky years ago and some of the rare malts used go back as far as 1963.
Peter Gordon, the fifth-generation descendent of distillery founder William Grant, said: ďThis exceptional 25 Year Old blended Scotch whisky is our way of celebrating each family memberís contribution to the success of Grantís whisky and our unique family history.
ďGrantís 25 Year Old is distilled in Girvan, a site built by our current life president Charles Gordon, this outstanding blend contains 25 whiskies from every region of Scotland with the most unique element being our Girvan Grain, the backbone of all our blends.Ē
Every bespoke bottle has been specifically designed to showcase the blendís rich amber colour and is presented in an individually hand-finished gift box adorned with gold engraved metalwork.
The Grantís 25 Year Old has an rrp of £210.†