The definitive top 20 of classic television programmes which have been lost by the BBC and ITV has been drawn up by the National Film Theatre. And an amnesty has been promised to people who might have illegally recorded the programmes so that they can hand them back.
The list makes astounding reading. Pop programmes, in particular, were thought to be dispensable. And so appearances on Juke Box Jury by The Beatles and the Rolling Stones were lost. Just two episodes have been kept of the original series, which ran for eight years from 1959.
There are also only two episodes from seven years of Thank Your Lucky Stars, another early pop programme, and only a handful of episodes from the 10 years of Sunday Night at the London Palladium, which features every variety act of the era. Incredibly only two episodes of Top Of The Pops from the Sixties survive.
But it was not only pop which was judged to be ephemeral. ITN has lost the first News At Ten, transmitted on 3 July 1967. The BBC discarded coverage of the first moon landing in 1969 with Patrick Moore and James Burke in the studio.
Comedy casualties include most of the Sixties episodes of The Likely Lads. Another collectors' piece would be Alan Bennett's series of sketches On the Margin from 1966. Not a single episode has been found.
Among the drama losses are Dennis Potter's 1967 play Message for Posterity and David Mercer's 1959 Armchair Theatre play No Trams to Lime Street. Another missing Mercer play, Madhouse on Castle Street, from 1963, features a straight acting performance from a 22-year-old Bob Dylan, who happened to be in Britain at the time. Dylan's was one of countless fascinating cameos among the lost programmes.
Ronnie Barker appeared in a 1965 version of A Tale Of Two Cities, which starred Peter Wyngarde, a version Wyngarde is very keen to see again. According to the NFT, it is believed that the tape was sent overseas and has been seen on Nigerian television - put on as a filler in between transmission.
The British Film Institute said yesterday that it would overlook any problems of illegality that might exist with tapes having been bought or sold in the past. "No questions would be asked" of people who brought in tapes of the lost classics, a senior official said.
A six-year hunt under a BFI/NFT campaign called "Missing Believed Wiped" has found some programmes not on the above list.
A 1958 episode of the rock'n'roll show Cool For Cats has been handed over by the show's director, Brian Taylor. It will be screened at the NFT on 17 October, along with other newly rediscovered programmes, including a half-hour play called Robert, directed by Ridley Scott, and a Fifties crime series, Saber of London, featuring Michael Caine.
Some of these have been handed in by producers and others who worked on the programmes. Some have been swapped in a thriving underground market which particularly exists for science fiction television. Some are on tapes or rolls of film that members of the public found in their attics. One that came to light in this way was a light entertainment programme called Hippodrome, hosted by a young Woody Allen sparring with a boxing kangaroo.
Veronica Taylor, of the National Film Theatre, said: "In the Fifties and Sixties pop and light entertainment were thought to be ephemeral. Opera and ballet were always kept because they were thought to be high culture. And sport was usually kept.
"Recently I asked the BBC if they had kept their version of Hemingway's A Farewell To Arms with Vanessa Redgrave. But they hadn't. These programmes are part of the heritage. Now it seems criminal to us that anyone could see The Beatles or Vanessa Redgrave or Dennis Potter and think 'we could wipe that tape and use it for 'Horse Of The Year'."
It has to be remembered, of course, that a two-inch tape in 1959 cost the equivalent of pounds 2,000, so there was great reluctance to keep programmes. But even though some programmes have been wiped, the NFT and British Film Institute are confident that copies of many do exist, perhaps from very early video machines or tapes sent overseas, often to army units (several Z Cars episodes recently turned up in a warehouse in Cyprus) or even from someone just pointing a film camera at a TV screen.
The recent "lost Steptoe" shows from the Seventies which have been restored and shown by the BBC turned up on a primitive video machine in one of the homes of the scriptwriters Galton and Simpson.
And, of course, some classics have simply been wrongly filed. The NFT has just found some episodes of the sci-fi series 'A' for Andromeda, which the BBC filed on the wrong shelf for over three decades. One might have thought that a programme called 'A' for Andromeda was not difficult to file correctly - but that's television...
The Programmes Being Sought
A for Andromeda (1961) - BBC
Armchair Theatre: No Trams to Lime Street (1959) - ABC
A Suitable Case for Treatment (November 1962) - BBC and other plays by David Mercer
A Tale of Two Cities (1965) - BBC
(and several other Sunday serials from the Fifties and Sixties)
The Crucible (1959) with Sean Connery, Susannah York - Granada (the final 18 minutes are missing)
Doctor Who (especially 'The Tenth Planet') - BBC
Emergency Ward 10 (1957-67) few survive - ATV
Juke Box Jury (1959-67) especially The Beatles - BBC
The Likely Lads (1964) - BBC
Madhouse on Castle Street (shown 13 January 1963) - BBC
Message for Posterity (shown 3 May 1967) - BBC
Coverage of the first moon landing, with Patrick Moore and James Burke in the studio - BBC
The first News At Ten (July 3 1967) - ITN
On the Margin with Alan Bennett (1966) - BBC
Opportunity Knocks (1956-77) - ITV
Out of the Unknown Series 3 (1969) - BBC
Sunday Night at the London Palladium (1955-65) - BBC
Thank Your Lucky Stars (1961-66) various episodes - ABC
Till Death Us Do Part (1966) many episodes - BBC