When you think about it, Johnnie Walker Blue Label is a little like the impressively large marine mammal that shares its colour.Like the blue whale, it’s rare, rather precious and, even if you don’t see one every day, it’s good to know it’s there.At around £150 a bottle Blue Label is always going to be something of a luxury. It might not be strictly necessary but we’d all be a little bit worse off without it. After all, you may not be able to afford it today but we all need something to strive for. Life would be pretty dull without targets.The Johnnie Walker range can be traced back to 1867 when Alexander, Johnnie’s son, first blended the whisky that we know as Black Label. Today, it’s the best-selling premium whisky in the world.The family has grown since then. Next came Red Label (c1909) to be joined eventually by Gold and Green Labels (formerly Johnnie Walker Malt). Blue came along in 1992.Unlike most of the whisky world it doesn’t carry an age statement, despite its superpremium price tag. Why?Maureen Robinson, Diageo’s Scotch liquid development manager and one of the original blending team, explains that the goal was to emulate the powerful character of a traditional 19th century blend.That’s an interesting challenge. Whisky was fuller flavoured back then, with a more pronounced taste and greater ‘peat reek.’ After all, as late as 1930, Aeneas MacDonald could write: “The convenient proximity of a peat bog is an economic necessity for a Highland malt distillery.” Which is hardly a sentence that could be written today. Its very matter-of-factness speaks eloquently of the taste of our drams.So creating Blue Label was, to a remarkable extent, an intellectual exercise; a theoretical construct in which a group of people, in the late 20th century, imagined what whisky would have been like more than 100 years ago.And not just any whisky. This was to be a super-luxury whisky – again, not a category that would have been well-known to drinkers at that time.Fortunately, they had several things on their side. Firstly, Sir Alexander Walker’s blending notebook, full of unrealised visions of blending perfection.Secondly, the full range of Diageo stocks (and Diageo’s buying power for any whisky it felt it lacked). And thirdly, it’s only fair to acknowledge, these Diageo folk do know rather a lot about whisky.They also had the Walker house style which tended towards the smoky, with an Islay influence clearly detectable (Caol Ila, Lagavulin and the now lost and muchlamented Port Ellen are part of the Diageo stable), so it was fortunate that fuller, darker and smokier were desirable characteristics in its ‘replica’ whisky.That’s certainly authentic. Writing just prior to 1900 in How to Blend Scotch Whisky the magisterial Barnard tells us: “Islay whisky, from its roundness and fatness, is essentially superior to all whiskies of its class for blending. Agood blend cannot be made without some Islay whisky in it, for nothing binds a blend together so well as Islay.” Barnard was writing on behalf of Mackie & Co, then proprietor of Lagavulin, which eventually joined the Distillers Company Ltd, and thus Diageo. The aristocratic, even blue-blooded link to Johnnie Walker is clear.For greater verisimilitude Blue Label is made up of a fairly short list of components: around 16 malts and grains, where a lesser blend might employ as many as 40. For the finishing touch, a number of the older malts come from distilleries now silent.The challenge is self-evident: eventually, they will all be used and, by definition, cannot be replaced. There’s a further twist, however. With the boom in single malts, they are increasingly desirable in their own right.Presumably the Johnnie Walker team has to fight the Diageo malt team, with a luckless stock controller holding the ring, to get access to the precious casks.The problem of declining stocks has, of course, been anticipated and a portfolio of carefully selected whiskies to replicate the lost flavours of the ghostly stills is being assembled. Therefore Diageo remains confident that the unique Blue Label taste will remain constant.And here the original decision not to declare an age comes into play. This gives the blender complete creative freedom: if a particular cask of a certain whisky is deemed ready, then it can be used, regardless of age. Blue Label makes great play of its use of ‘younger whiskies’ alongside more venerable spirits.This is, of course, a relative term: ‘younger’ in Blue Label terms means at least 12 to 15 years old, though that is younger than the senior citizens, some up to 60 years old, that join the blend.So this is a remarkable blend and, in a perverse sort of a way, quite a bargain.Where else do you get the taste of long-lost single malts, great age (even if not specified) and a rare display of virtuoso blending skills in a single bottle?What’s more, while nicely packaged, it’s not particularly lavishly dressed, meaning more of your money goes into the whisky.Which is where it should be.I was, I have to admit, a little sceptical prior to tasting this (even whisky writers don’t sup on Blue Label every day), but a few nips removed the doubt. It is every bit as complex, satisfying, rich and rewarding as promised.And, for the truly privileged, it gets even better. You can drink (as opposed to collect) Johnnie Walker Blue Label Cask Strength, a limited edition release to celebrate the 200th anniversary of John Walker’s birth in 2005.At a typical United Kingdom shelf price of £2,000 a bottle, though, the cost isn’t just in the whisky. You are definitely paying something of a premium for the exclusivity and the exquisite Baccarat packaging.There’s a ritual to drinking Blue, according to Diageo. It suggests trying it neat, having first prepared your palate with a sip of iced water. The result is an explosion of flavours, for which the nose (rich and promising with hints of mature citrus and dried fruits) can only partly prepare you.The flavour rolls on – honey, nuts, rose water, some smoke, aromatic wood notes – but all balanced and sustained, with a lingering finish.By comparison, bottled at 60% and non chill filtered, the Cask Strength is a leviathan of a whisky – fatter; more intensely brooding; dark, mysterious and capable of great depth. There she blows!It’s a blue whale moment.