In recent years, quality European drama has become so familiar to British viewers that Nigel Farage may well be experiencing night terrors. For most countries, non-native content is nothing unusual, as anyone who has found Towie improbably belching itself out of a hotel telly abroad can confirm, but the assumption had reigned for many years that anything featuring foreign tongues would make Britons squirm away in horror. Nowadays, continental drama routinely outclasses British counterparts with the ease of Barcelona taking on Grimsby Town. And not just critically: from the 30 most-watched programmes since BBC4 started in 2002, 14 places are taken up by episodes of Scandinavian thrillers The Killing, The Bridge and Borgen. It's a mystery why subtitled drama was missing from British television for so long.

Once, foreign-language shows were aimed largely at specific audiences. A classic example is the 1988 Hindi series Mahabharat, an epic tale of feuding princes and their scheming siblings, which attracted up to 5 million viewers in a Saturday afternoon BBC2 slot. Then there were the imported dramas broadcast because they were weighty, such as 1984's Heimat, an enthralling dramatisation of ordinary lives in 20th-century Germany. Despite these successes, the arrival of digital television saw subtitled programming all but disappear from mainstream networks. Niche channels provided an outlet for many such programmes, allowing newly defensive terrestrial networks to shove anything remotely "edgy" aside.



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Even Channel 4, which had led the way in foreign-language content, moved on. "When it had to sell its own advertising in 1993, it stopped having to be so quite self-consciously alternative. Dropping subtitled drama was an obvious way to meet that need," suggests Steve Williams of television history website TV Cream. "In the 80s it was showing things like Xerxes at 6.30pm as if it were a normal drama, because that was the kind of thing it did. That was the first to go."

Aficionados of foreign television now had to hunt for imported boxsets and English subtitles. That is, they did until BBC4 made the bold decision to add international drama to its eclectic menu. While Brazilian favela drama City Of Men tested the waters in 2004, following the success of Fernando Meirelles's film City Of God, it took the Gallic grit of French cop series Spiral in 2006 to provide BBC4's first subtitled sleeper hit. That, of course, was followed by Denmark's The Killing, the show that proved must-see TV can be in any language. Settling into the now-traditional Saturday night subtitled drama slot, by the conclusion of its first series in 2011 The Killing routinely topped the BBC4 ratings.

Post-Killing, other channels have flocked to subtitled drama. Sky Arts snapped up Spain's Downton-esque period piece Grand Hotel, Italian sleuth-fest Romanzo Criminale and Israel's Hatufim, which was the inspiration for US smash Homeland. Even FX, normally dedicated to US imports, introduced viewers to brutally brilliant French cop show Braquo.

Now that international drama has made it to the mainstream, Channel 4 is set to treat viewers to hit French series The Returned. Much like Breaking Bad, Dexter or Ripper Street, the premise sounds ludicrous when crammed into a nutshell: a zombie-cum-slasher-cum-crime drama centred on a mute adoptee and a reanimated butterfly. The Returned handles the madness in such an effortlessly controlled manner, however, that it is easily among the best that European drama has to offer.

'The positive critical reception, word of mouth and the rise of Nordic noir fiction has seen a snowball effect on the popularity of subtitled drama'

The Returned

Were it not for the success of The Killing et al, The Returned might have found itself quietly picking up a small but loyal audience in a graveyard slot on E4, or the network might have preferred to wait for the forthcoming US remake. "It's a risk putting a foreign-language drama on Channel 4 because it is inevitably more niche in appeal," says the channel's chief creative officer, Jay Hunt. She adds, however, that "The audience will often go with you on a show if they can see the quality."

So is it luck, judgment or a new appetite that's led to the current influx? "It seems to have been a gradual process," suggests Sue Deeks, head of programme acquisitions for the BBC. "Since Spiral was first shown, the popularity of subtitled drama has steadily increased. The familiarity people already have with crime drama has helped viewers adapt to programmes like Spiral and The Killing which, combined with the positive critical reception, word of mouth and the rise of Nordic noir fiction has seen a snowball effect on the popularity of subtitled drama."

Another possible factor is that international drama offers escapism. While the crime plots may not necessarily be distinct from those faced by fictional British detectives, the sense of unfamiliarity offered up by tales from continental climes adds a sense of freshness. At its best, scripted television exists as a gateway into another world, and now that audiences have discovered subtitles need not be a barrier to suspension of disbelief, international drama offers a new escape from everyday life. Or, at the very least, from Casualty and Mrs Brown's Boys on BBC1 •

The Returned starts Sun, 9pm, Channel 4. Check back after the opening episode for the first of our weekly series blogs.