The Avengers, which made its debut on British television 60 years ago this month, was a harbinger of the monumental changes in popular culture that would reshape young lives everywhere. The pop-surrealist thriller series was an early disrupter, predating such key early 1960s moments as “Love Me Do”, the Profumo affair and Andy Warhol’s 32 Campbell’s Soup Cans.

Later in the decade, when the programme reached its peak, its bold designs, gently ironic scripts and demented plot-lines briefly threatened to subvert the western narrative tradition. Who cared about what was happening, when what was happening looked so good and sounded so clever?

It took its time to unleash its radical intent. The first episodes were relatively orthodox outings in spy adventure, although the show’s title hinted at its disrespect for coherence: never was it made clear who was being avenged, nor for what reason. Patrick Macnee, as secret agent John Steed, was recruited for his witty hauteur — “the essence of an English gentleman”, producer Leonard White called him — but the show did not really take off until he was joined for its second series by Honor Blackman’s Cathy Gale, a cool, blonde anthropologist who wore leather and dispatched assailants with expertly executed judo throws.

The dash of sexual spice between the two leads attracted young audiences, and improbable advocates. Novelist Kingsley Amis grasped the programme’s irreverent tone immediately. “These are a pair of heroic freelancers,” he wrote of Steed and Gale in the TV Times in 1964, “inspired amateurs who knock off a couple of worldwide conspiracies in the intervals of choosing their spring wardrobe. All this is, so to speak, a wink at the audience, a joke shared with them.”

The high-class banter between the protagonists was a “satirical nudge” that required viewers to show a novel, more sophisticated, kind of “mental agility” as they watched in this new TV age, added Amis. No less agile were the off-screen exchanges between the pair: Macnee’s attempt at a pass on Blackman was bracingly rebuffed, as he recalled in his autobiography: “This is neither the time nor the place, I’m sweating like hell, my feet are killing me, I smell like a polecat and the answer’s ‘No.’ ”

That misadventure notwithstanding, Macnee and Blackman sought to exploit their screen chemistry with the 1964 release of a single, “Kinky Boots”, a miserable song which performed miserably (until its re-release in the nostalgia-ridden 1990s). The Avengers was becoming part of the pop culture conversation, and its makers aware that the show’s stylistic innovations were more important to its fans than the more traditional concerns of narrative tension, suspense and credibility.

“Every episode [has] to be about something new and presented in an exciting way,” pronounced story editor Richard Bates ambitiously, buoyed by the era’s lust for novelty. When Blackman announced her departure from the series in 1963 to play the spy Pussy Galore in the new James Bond film, Goldfinger, any sense of panic from the showrunners was offset by their discovery of Royal Shakespeare Company actor Diana Rigg to replace her.

Rigg’s sexual allure was set centre stage: her name would be Emma Peel, or “M[an] Appeal”, and she would announce herself in a new opening credit sequence, popping a champagne cork held by Steed with a shot from a gold revolver. The bottled frothed over, the actors smirked. The sequence concluded with some nonsense with swords and carnations. Here was a new level of knowingness, or sophistication, for an audience ready to forsake any earnestness for shaded, on-trend wit.

The show’s pretensions — Peel’s martial arts moves were said to be based on the “angular poses and attitudes of the Hindu deity Shiva” — were transparently tongue-in-cheek, its savvy actors complicit in the humour. Rigg’s coolness under duress distanced her from the absurdity all around her, which, in the coolest of decades, made her ever more alluring. “I always seemed to be strapped to a dentist’s chair with my feet in the air,” she once recollected with faux primness.

As for the erotic frisson between Steed and Peel, it was of course as fake as the gaudy sets, a simulacrum of flirtation. The Avengers was the perfect programme for its time, devoured by an existentially unsure Britain that was openly wondering whether it still adhered to traditional values (the dapper, Edwardian Steed) or was keener instead to explore the highly charged, sexually liberated world of its youth. The urgency of that debate was defused here with what was essentially a series of fabulously attired send-ups. No character on The Avengers was allowed to have real feelings. Television was reflecting the country on the cusp of profound moral change in real time, but it was enjoying itself hugely in the process.

The plots, in the meantime, got crazier. In 1967’s “Epic”, from the fifth series, Peel is kidnapped by a Teutonic film director named ZZ von Schnerk, who is filming a movie entitled The Destruction of Emma Peel, for which he needs to kill her in real, or reel, life. The self-referentiality was off the scale now. “Gloat all you like, but just remember I am the star of this picture,” says captive Peel to the villainous director, and anyone interested in meta-texts.

Like so many of the fashions of the 1960s, Rigg only lasted a couple of seasons. She left to star in her own Bond film, 1969’s On Her Majesty’s Secret Service, in which she proved that her range extended further than understated self-mockery (in fairness, she had also already played Cordelia opposite Paul Scofield’s Lear) by providing one of the franchise’s few genuinely heartbreaking endings. Peel’s farewell to Steed was itself a rare poignant moment, a peck on the cheek with a final piece of womanly advice: “Always keep your bowler on in times of stress. And watch out for diabolical masterminds.”

The next series saw Macnee’s new partner, Linda Thorson, gamely attempting to succeed the unsucceedable, her chances subverted from the start by the producers’ determination to make her more “feminine”, and the series more “realistic”. Those decisions were a death knell. The Avengers’ moment was over, and the show was cancelled in 1969.

Attempts to revive the brand, through the anaemic The New Avengers in the 1970s, and 1998’s disastrous movie version, only emphasised the extent to which the original series depended on sociocultural context for its success. Rigg and Blackman were both lost to us last year, but you can still catch the show — their show — on most days of the year on UK daytime TV (currently ITV4) and it remains a daft, urgent thing of beauty.

An online event celebrating the 60th anniversary will be held on January 29. Tickets at ourscreen.com

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