Question: George Anthony David Haygarth stars in "Unman, Wittering, and Zigo", a British film based on a radio drama from what year?

Context articles: Battalion of Saints
Blood Son
Too Much of a Good Thing (radio play)
Let George Do It (radio)
Dark River (1990 film)
Tony Haygarth
Empire of the Air: The Men Who Made Radio
Unman, Wittering and Zigo (film)
Tony Scott
The Ghosts of N-Space

Battalion of Saints is a hardcore punk rock band from San Diego, California that was founded in 1980.
 The band went through numerous lineup changes before touring the United States and Canada from 1984-1985 with George Anthony, Chris Smith, James Cooper and Joey Wrecked (Maya).
 Half-way through the 55-city summer 1985 tour, the road manager, Captain Scarlett(David Lloyd) replaced James Cooper on bass.
 The band officially broke up in 1985.
 Singer George Anthony re-formed the band in 1995 with Terry "Tezz" Roberts (veteran of British punk bands Discharge, Broken Bones, and U.K. Subs), and signed to Taang!
 Records, which reissued most of their material on the "Death-R-Us" CD.
"Blood Son" is a short film by Michael McGruther.
 It is the first production of BuffaloNickel Films.
 It is based on the short story "Drink My Red Blood" that was written by Richard Matheson.
 It was first published in 1951 and was also adapted into an episode of the British Radio Drama Book at Bedtime, where it was read by David Tennant.
Too Much of a Good Thing is a radio play, recorded entirely on location, as if it were a film, by Mike Leigh.
 Liane Aukin, the 'midwife' of the project, a BBC radio producer, knew Leigh through her brother David, the general manager at Hampstead Theatre.
 She had initially asked Leigh to revive "Abigail's Party" on the radio, but he preferred to supply an original piece.
 Ronald Mason, the head of radio drama, was enthusiastic and allocated £5000.
Let George Do It is an American radio drama series produced from 1946 to 1954 by Owen and Pauline Vinson.
 Bob Bailey starred as private investigator George Valentine; Olan Soule voiced the role in 1954.
 Don Clark directed the scripts by David Victor and Jackson Gillis.
Dark River is a 1990 British film, featuring Tom Bell, Siân Phillips, Kate Buffery, Ian McNeice and Tony Haygarth, among others.
 Dark River was an official selection at the 1990 Montreal Film Festival and the Ghent Film Festival of the same year.
George Anthony David Haygarth (4 February 1945 – 10 March 2017) was an English television, film and theatre actor.
Empire of the Air: The Men Who Made Radio is a non-fiction book by Tom Lewis, a history of radio in the United States, published by HarperCollins in 1991.
 The book was adapted into both a 1992 documentary film by Ken Burns and a 1992 radio drama written and directed by David Ossman.
 The source of the title is from a quote by Lee DeForest.
Unman, Wittering and Zigo is a 1971 British thriller film directed by John Mackenzie and starring David Hemmings, Douglas Wilmer and Tony Haygarth.
 It is adapted by Simon Raven from Giles Cooper's 1958 radio drama "Unman, Wittering and Zigo".
 A new teacher arrives at a school and begins to suspect his predecessor was murdered by the pupils, though his suspicions are written off as paranoia.
 He sets out to prevent the same fate from befalling him.
Anthony David Leighton Scott (21 June 1944 – 19 August 2012) was an English film director and producer.
 His films come from a broad range of genres, including the action drama "Top Gun" (1986), action comedy "Beverly Hills Cop II" (1987), auto racing film "Days of Thunder" (1990), action comedy "The Last Boy Scout" (1991), romantic dark comedy crime film "True Romance" (1993), submarine action film "Crimson Tide" (1995), psychological thriller "The Fan" (1996), spy thriller "Enemy of the State" (1998), spy film "Spy Game" (2001), action thriller "Man on Fire" (2004), sci-fi action thriller "Déjà Vu" (2006), thriller "The Taking of Pelham 123" (2009), and the action thriller "Unstoppable" (2010).
The Ghosts of N-Space is a radio drama based on the long-running British science fiction television series "Doctor Who".
 It was recorded in 1994 and finally broadcast in six parts on BBC Radio 2 from January 20 to February 24, 1996.
 This was the second Third Doctor radio play, following "The Paradise of Death" in 1993.
 Plans for a third were scuppered by the death of Jon Pertwee in May of that year.