To celebrate BBC2's 50th anniversary, the channel exhumed an hour of so-called hidden treasures from The Comedy Vaults, including un-aired pilots, cult classics and first television appearances from comedy legends such as French & Saunders, Steve Coogan and Billy Connolly. There was even rare archive footage of Harry Hill with hair.

Monty Python's Eric Idle was also on hand to puncture the general air of self-congratulation, suggesting BBC2 should actually be charged with crimes against humanity for losing or wiping so many tapes containing classic comedy episodes and performances.

One tape the station would have done well to lose featured the band Madness, starring in an eponymous sitcom written for them by Ben Elton and Richard Curtis. It would be hard to pick out one band member for opprobrium, as they were all so dreadful.

It's criminal to keep these comedy gems locked away

It is criminal that the BBC has been sitting on thousands of hours of historic material for decades, letting the cannisters disappear under layers of dust and never publishing a catalogue of what's actually in their film warehouses -let alone reshowing them.

Review: The Comedy Vaults

The result was certainly a treat for comedy geeks in parts, but there was also a fair bit of padding, pulling in bits from sketch shows that many will remember.

The Comedy Vaults - TV Review

The Comedy Vaults' problem was that it showed a lot of lamentable stuff by people whom we now revere learning their craft at the licence fee payers' expense.

The Comedy Vaults: BBC Two's Hidden Treasure, BBC Two

More questions than answers in this trawl of 50 years of comedy clips.

The Comedy Vaults review

There were the great sketch shows from the Sixties, Seventies and Eighties that, inexplicably, haven't been repeated since.

Radio Times review

As part of its 50th birthday celebrations, BBC2 has tiptoed downstairs to the vaults, cleared the dust from the shelves and picked some little-seen and little-remembered comedy treasures from the past half-century.

It has an enviably rich archive to trawl, one full of familiar faces. There are surprises, too, including the unbroadcast pilot of QI. Early BBC2 stalwarts aren't forgotten: there are sketches from Peter Cook and Dudley Moore, and Spike Milligan, whose thoroughly surreal and bizarre Q series ran for well over ten years.

We also get to see an early Borat work-in-progress from Sacha Baron Cohen, as an Albanian called Christo.

10 great forgotten comedy shows

As BBC Two unearths some old comic gems for a new documentary, Michael Hogan looks at 10 shows that have been forgotten by history.