TWELFTH NIGHT. Channel 4 Schools. January 17, 9.30-11.12am

Where exactly is Illyria? It might be located, in literal terms, somewhere in the north of what used to be Yugoslavia, near the Italian border, but, if Shakespeare’s Twelfth Night is sprinkled with Italianate names - the Duke Orsino, Olivia, Viola - there are plenty of hints that we are really in a version of Elizabethan London. Antonio advises Sebastian to stay at the Elephant, in “the south suburbs”, Feste refers to the bells of St Benet, a City of London church within walking distance of the Middle Temple, where one of the earliest performances of the play took place before an audience of lawyers, and Olivia’s house guests have the undeniably English names of Sir Toby and Sir Andrew.

For his television adaptation of the play, director Tim Supple has conjured an imaginary, modern-dress London while maintaining a Mediterranean feel for the great houses of Orsino and Olivia. But for him this is no escapist romance; it is an analysis of the emotional journeys being taken by a group of people, some of whom are failing to face reality. For Viola and Sebastian, there is a real journey to undertake. Most actors playing the shipwrecked twins invent a “back story” to help them develop their characters, giving reasons for their running away from home and some understanding of their isolation; Supple has made this explicit: flashbacks show the siblings fleeing an Asian country in turmoil. Viola arrives, like many an asylum seeker, without much idea of where to go or what to do until she decides to work for the well-heeled Orsino.

Supple sees the Duke as “a cross between a playboy royalty figure and a celebrity who lives in a world of his own fantasy in a modernist mansion overlooking the sea”. He has time on his hands and fills it listening to music and dreaming of the bereaved Lady Olivia. She is similarly leisured, but has a completely different attitude to privilege and responsibility, and is probably (in this production) from an old aristocratic family, but with media connections. She is a religious woman, expressing shock and grief at the loss of her brother (shown in flashback to have died in a car crash) by constantly attending her own candle-filled chapel. Despite the updating, Supple has in mind the religious divisions of the 16th century, soon to play a role in the English civil war. And Olivia, he says, has another side to her - a capacity for passionate love. “She lurches from one extreme to the other; the events of the play help her to find a balance.”

Olivia’s steward, Malvolio, is a po-faced managerial sort, “a real threat”, says Supple, “to the continuance of people’s lives in Olivia’s household. He is absolutely in love with Olivia, or possibly with her status.” The central comic scene in which Maria, Sir Toby and their friends leave a letter, purporting to come from Olivia, in Malvolio’s path to persuade him to appear smiling and wearing yellow, cross-gartered stockings, works especially well with Supple’s modern treatment. The conspirators watch the proceedings on a security camera and are thus free to squeal and comment. The device also provides an explanation for the sudden appearance of Fabian: he is Olivia’s security guard.

Supple uses film techniques such as flashback to help him meet the time constraints of television and has cut judiciously to fit his allocated hour and 40 minutes. Much of the punning wordplay, the humour of which is difficult to appreciate in a modern context, has gone, although he says this would have been included in a fully fledged production. His excellent multicultural cast - Orsino is played by Chiwetel Ejiofor, recently seen in Stephen Frears’s film Dirty Pretty Things, and Viola is Parminder Nagra from Bend it Like Beckham - reflects the diversity of 21st-century England. Viola and Sebastian occasionally lapse into Hindi (subtitles provided).

So, is anything lost in Supple’s generally engaging approach? Isn’t this a sombre version of the familiar comedy, with more than the usual emphasis placed on the themes of death and loss? And isn’t Sir Toby an unpleasant reprobate rather than a bon viveur and Malvolio a competent manager who doesn’t at all deserve his dreadfully cruel treatment at the hands of Maria and Sir Toby?

For a start, says Supple, the word “comedy” is misleading. To Shakespeare’s audience, “it merely meant the plays were about ordinary people”. He agrees that Sir Toby, like a lot of drunks, can be manipulative and vicious, but “he’s a lot of fun too and is loved by a number of people. Malvolio is a serious official and a Puritan - he’s only foolish if you don’t agree with him. You shouldn’t need broad-accented buffoonery to bring out the humour. There is a satirical edge to his character.”

If the ending, slightly rearranged by Supple, seems subdued it is touching, allowing Olivia to recall her grief and to express the understandable muddle of her feelings. This is a truly filmic Twelfth Night which takes advantage of the intimacy of the camera to produce what Supple accurately describes as an “emotional, soulful version of the play, about the interior lives of the characters”.

Twelfth Night will be broadcast on mainstream Channel 4 later this year