Can a box set save your marriage? My husband simply nodded with sage satisfaction. Don had been his suggestion - indeed, he'd been quietly insistent that the box set of Mad Men (seasons 1-4) would be the answer. But the answer to what? Deep down, ladies, I think you already know. The answer to those married conundra asked (generally by women, with varying degrees of whingeyness) the length of the land every Saturday night: why do we never do anything together? Why are we watching separate televisions in different rooms? Why am I in bed hours before you put in an appearance? It doesn't have to be Don, of course. It could be Tony Soprano - and all you trailblazing early adopters out there, I salute you. Or Detective Lester Freamon in The Wire; or Deputy Superintendent Sarah Lund in The Killing (1 and 2). Because when it comes to bonding, middle-class style, the box set rules supreme. There is nothing - nothing, I tell you! - more fabulous, more consolidating, than curling up on the sofa with two glasses of chilled white and seven red-hot seasons of Hustle. Apart, perhaps from 44 discs of The West Wing, or 68 episodes of thirtysomething (yes, folks, get out your credit cards for a modern classic); or seasons 1 to 3 of Damages - that's a helluva lot of togetherness in anyone's book. The thing about box sets is they are addictive. Even the most time-starved professional or put-upon parent finds them impossible to resist. In truth, being up to date with any newly released box set signals to the world that you are both discerning and able to prioritise what's really important in life. Or rather reprioritise, seeing as you were too busy, disorganised or just plain knackered to tune in - or if you did tune in, to stay awake - when they were broadcast first time around. But the flip side is box set syndrome, also known as the Box Set Blues, a thoroughly modern affliction. "Of course there will always be those left anxious by the pressure to keep pace with seasons one to six of The Hills or Brothers and Sisters," admits Jim Murphy of the Future Foundation think tank, with a note of genuine sympathy. If we're invoking the pathology of addiction then maybe we should consider the theory of narco-television, power-injections of such artistic/dramatic luxury that one just cannot stop licking the remote. It's not a pretty image to conjure up - but there's worse to come. Like all addictions this must lead to depression, bingeing, wrecked intimacies, cold turkey, late-night fixes, therapy, priories for the mind, a falling from wagons. He's spot on about the bingeing, but I'm not so sure about wrecked intimacies: entre nous, when Borgen Prime Minister Birgitte Nyborg and her husband Philip's marriage fell apart (they were never once seen watching a box set - draw your own conclusions), I was so devastated I insisted my husband and I have make-up sex immediately after the final credits rolled. That's the thing about the box set; when you spend so long in the company of characters over a short period, you become much more emotionally attached to them than you would if you only watched weekly; and as life imitates art, it strengthens your feelings towards the person you enjoyed the experience with. And that's a phenomenon that is being joyfully exploited in the world of online dating, where box sets are the new "country walks and meals out." Listing those you own in your profile makes it clear what sort of person you are: bang on trend, but also likely to commit (at least to hours of television, if not to an actual person). As one single friend puts it: "Saying you like box sets is a coded invitation to lounge around, quite possibly in bed, for days at a time, which is a great start to any relationship." But self-love can be as big a motivator as any desire to attract a mate and there is something rather consoling about immersing oneself in a parallel universe. "The middle classes are drawn to ownership and to sense of control offered by a box set," says Maddie Yorke, who writes for the shamefully compelling website The Middle Class Handbook. We love how much quality relaxation time these discs represent. Box sets have coincidentally risen to power at a time when more and more people live alone, and it may be that they plug what is the so-called "community gap." Stories are legion of friends and family who disappear for weeks at a time, lost to the thrall of a new box set. Or four. An 18-month delay in the production of the Golden Globe-winning series Mad Men, the fifth season of which premieres on Sky Atlantic on March 27 , has given slackers and latecomers who missed it on BBC4 the chance to mug up just in time (something which slightly irks the die-hards who've been there since the beginning, but it all evens out eventually). "A box set, for a middle-class person, seems to offer a huge amount more personal - not monetary - value than you get from just watching episodes on television as and when they come on," adds Yorke. That maximises the sensation of being defined by, or gathering some sort of self-worth from, a television show that you love. A box set - the right box set - is more than a few hours" entertainment. It is a symbol of our values, a totem of our class and, at best, a subtle form of one-upmanship. In an age when our music is played from a docking station and our books are on Kindle, how else can visitors to our home assess and admire our impeccable taste and our unerring ability to stay au courant? The best, worthiest, classiest box sets are always displayed towards the front of the shelf to make sure visitors can see them. These will be any or all of the following; The Killing, The Wire, 24, The Thick of It, The West Wing, Six Feet Under, Mad Men, The Sopranos and Downton Abbey. You're also likely to find Sex and the City, The Office and Frasier, but you'll have to rummage further back to find them because, while perfectly acceptable, they lack the fashionability factor and cachet of this year's crop, namely; Borgen, Boardwalk Empire, Call the Midwife and Sherlock. If you haven't got them yet, then simply wait until Christmas. "Box sets are not just must-haves, they've become must-gives," says Dan Halliday of the cutting edge creative agency Not Actual Size. They are the new default present for middle-class men; a sort of scented candle you can watch. Watch, and indeed flaunt. When the Camerons entertained the Obamas at home last May, the widely published photo opportunity - Michelle and Samantha side by side on a mustard sofa - was pored over like the Rosetta Stone as commentators sought to analyse those pivotal box set titles on the shelves behind. "Right behind the Camerons was a book/DVD shelf which had, of course, been carefully vetted in advance," says Halliday. Cameron did well with Band of Brothers, one of the top five biggest-selling box sets ever, and 24 was there. But he was badly let down by Michael McIntyre; it's obviously a middle-Britain favourite, but on a box set? The comedy Friends, once such a trailblazer, first on video, then on DVD, is another no-no. Although it was historically a show that men and women would watch together, it's now deemed too girly for most blokes to countenance. The secret of a truly successful box set is that it is non-gender specific. Nor is language a bar, which explains why box sets have become Denmark's most notable export. In our house the Euro-box set du jour is the slick French cop show Spiral, with its mélange of sex, death, torture and treachery played out by a cast of morally ambiguous misfits. It's an emotional roller coaster this box set business and no mistake. But like all full-throttle, extreme rides, we find ourselves craving the adrenalin; and if the thrills and spills make us cling tighter to those sharing the sofa, so much the better.