Why was a brilliant BBC serial kept in its most secret vaults?

BBC Four announced this morning that ‘The Roads to Freedom’ will play on the BBC for the first time since the 1970s on Wednesday 27 July. In May, Peter Hitchens asked why the BBC had kept it in the archive… 

If someone had managed to bottle the essence of the 1960s – the exciting, adventurous bits – wouldn’t you want to take at least one deep draught? I certainly would. I sometimes long for the power to recreate that odd, dangerous, thrilling time, if only to see if I have got it right in my memory. In fact, they did bottle it. But nobody is allowed to taste the vintage. Well, almost nobody, as we shall see.

The BBC possesses, beyond doubt, a full recording of its 13-part 1970 dramatisation of Jean-Paul Sartre’s The Roads to Freedom trilogy. Set mainly in Left Bank Paris at the very end of the 1930s, its action prefigures the late 1960s quite remarkably.