When the movie world looks to TV land, it's usually to capitalise on the ratings-topping popularity of a beloved television show. Our multiplexes are littered with big-name films based on big-name telly shows.
But sometimes the TV version is pretty obscure. Here are eight movies that you might not know started life on the small screen.
1. Trance
Though he didn't make it until 2013, Danny Boyle's relationship with this mind-bending thriller stretches all the way back to 1994, when a novice screenwriter by the name of Joe Ahearne pitched his script to the Shallow Grave director.
But Ahearne wanted to direct it himself, which Boyle thought too big a job for a first-timer. Eventually Ahearne did direct it, as a modestly budgeted TV movie in 2001, starring Christopher Cazenove, Neil Pearson and Phil Davis, but Boyle never forgot Ahearne's script and with regular writing partner John Hodge set about crafting his own version (Ahearne gets a 'story by' credit on the movie).
James McAvoy headlined as the art auctioneer who becomes mixed up with a group of criminal partners after a priceless painting is stolen, with an impressively menacing Vincent Cassel as the gang's vicious leader.
2. Traffic
Steven Soderbergh's thrillingly urgent, intricately plotted epic about the international drugs trade won a lorry-load of awards when it was released in 2000, including a Best Adapted Screenplay Oscar for writer Stephen Gaghan.
Traffic wasn't adapted from a book, but from a 1989 Channel 4 series (our version was titled Traffik, mind). Simon Moore (The 10th Kingdom) created and wrote all six episodes of the original series, which headlined Bill Paterson as a British Home Office minister engaged in combating heroin importation from Pakistan.
3. Scum
Ray Winstone's calling card was seen as too hot to handle by the BBC after it was made in 1977 and was pulled from broadcast. Roy Minton and Alan Clarke's Play for Today concerned the brutal reality of life inside a British borstal and centred around the charismatic but savage Carlin, played by a teenage Ray Winstone.
Undeterred, Clarke remade it as a feature film two years later, keeping most of the same cast (though Mick Ford would replace an unavailable David Threlfall as the wily, defiant Archer), upping up the violence and F-bombs, but jettisoning a gay subplot. The original version was finally screened in 1991 (not by the BBC mind, but on Channel Four).
4. The Firm
No, not the Tom Cruise / Sydney Pollack thriller.
There are plenty of cor-blimey turkeys on lad-flick director Nick Love's CV, but this 2009 movie is probably his finest effort. But then the source material was pretty good to begin with, as it's actually a remake of a 1989 TV movie directed by Scum's Alan Clarke and headlining Gary Oldman as the leader of a hooligan firm known as the ICC (Inter City Crew).
Love's version refocuses the story away from Oldman's character (played here by Peaky Blinders' Arthur Shelby actor Paul Anderson) and on to one of his starry-eyed followers (Calum MacNab) as well as shifting the action from 1989 to 1984.
5. Edge of Darkness
2010's Edge of Darkness was meant to be Mel Gibson's big-screen comeback, a nail-biting thriller that marked the actor's first leading role in eight years. But the movie failed to match the success of the TV series that it was based on, a BBC six-parter that had aired 25 years before.
In the critically love-bombed original, Bob Peck starred as a policeman who finds himself drawn into the murky world of government cover-ups and nuclear espionage after the death of his eco-activist daughter.
A lead-lined TV classic, it won a Best Drama Series award at the 1986 BAFTAs, as well as a Best Actor gong for Peck, and was placed 15th on the British Film Institute's list of the 100 Greatest British Television Programmes.
Gibson's version (which was, incidentally, directed by the original's Martin Campbell) didn't fare quite so well, grossing just $81.1 million, against a production budget of $80 million.
6. 12 Angry Men
Sidney Lumet's lean and keen 1957 movie is rightly regarded as a big-screen masterpiece, but how many know that it was based on a TV play originally broadcast live on CBS in 1954?
Less polished than the film and lacking the solid, scene-stealing presence of Henry Fonda, it does however share two actors in common – Joseph Sweeney (the old man) and George Voskovec (the immigrant), who play Juror #9 and Juror #11 respectively in both versions.
The TV play was thought lost for many years, only for a complete copy of the hour-long show to be found in 2003.
Here it is, you lucky people:
7. Brimstone and Treacle
When Brimstone and Treacle hit cinemas in 1982, it would have been the public's first taste of Dennis Potter's fiery tale of a man who may or may not be the Devil, worming his way into a gullible couple's house in order to molest their disabled daughter. (Different times...)
But a few may have remembered newspaper headlines from six years before, when the BBC's top brass decided to ban its own production of the play. Alasdair Milne, then the BBC's head of programmes, recalled being "almost physically sick" after watching it in advance of the planned transmission, deciding that the drama was likely to be found "repugnant" by much of the audience and should be pulled.
The later movie version retained a cast member in Denholm Elliott as the bitter husband and father, but replaced the impish Michael Kitchen (as the is-he-or-isn't-he Devil) with, ahem, Sting. The BBC's (superior) version was finally aired in 1987.
8. Shadowlands
Richard Attenborough's weepy true-life story about the love affair between The Lion, the Witch and the Wardrobe writer CS Lewis (Anthony Hopkins) and American poet Joy Davidman (Debra Winger) is one of the director's greatest films, but some audiences in 1982 might have experienced a strange sense of deja vu.
In fact, Shadowlands had begun its life as a 1985 TV play, again by writer William Nicholson starring Joss Ackland as the shy, introverted novelist and Claire Bloom as the ill-fated Joy. The original won a BAFTA for Best Play, while the movie version scooped Hopkins a Best Actor film BAFTA.
