By Caroline Briggs
BBC News Online entertainment staff
Gerald Priestland was the first "face" on BBC Two
BBC Two is in celebratory mode for its 40th anniversary, much as it was when it launched on a spring evening in 1964, billed as a night of music, comedy and celebratory fireworks.
But as last-minute rehearsals were drawing to an end, a fire at Battersea Power Station plunged Television Centre into chaos.
A blackout across most of west London meant BBC Television's glittering launch of their new channel was anything but.
Instead of presenter Denis Tuohy introducing Cole Porter's Kiss Me Kate, the channel hastily launched into a short news bulletin from Alexandra Palace.
But the bulletin, read by the late Gerald Priestland, was itself dogged by problems with the whole report broadcast without sound for the first two-and-a-half minutes.
BBC Two's first night did not go as planned
The rest of the launch evening consisted of test cards reading "BBC will follow shortly" interspersed with characteristic BBC-style apologies.
Tuohy, who was to be the first "face" on the new channel, said it was a nerve-wracking evening all round.
"The sense of occasion really had us fired up and I was feeling very nervous," he told BBC News Online.
LAUNCH NIGHT SHOWS
7.20pm - Line-up: with Denis Tuohy and John Stone
7.30pm - The Alberts Channel Too: a new television network opens
8.00pm - Kiss Me Kate: starring Patricia Morrison
9.35pm - Arkady Raikin: the Soviet Union's top comedian
10.20 - Off with a Bang: fireworks from Southend pier
10.35-11.00pm - Newsroom
"We had been rehearsing back-to-back all day and we went up to the BBC bar for a drink to settle our nerves.
"When I went back down to the gallery with about half an hour to go, I noticed all the television screens were blank and there were a lot of people shouting something about Battersea."
Robert Longman, who was in charge of engineering that night, recalls trying to negotiate the confusing corridors of Television Centre with a candle stuck in a paper cup as they desperately tried to find a way to get the new channel on air.
"It got to about 6.30pm when I noticed that the power frequency was falling slightly... then we lost power completely," he told BBC News Online.
"I went around telling everyone that we would be able to sort it out and not to panic... then we found out the whole of west London had gone."
"I just froze and thought 'oh dear', because it was an engineering problem - my problem - and the place was packed with people.
"In the end we just sent everyone up to the BBC Club for a drink where there was emergency lighting."
The candle in the darkened studio became an iconic image
Mr Longman said they tried to find emergency feeds to get on them on air for the 1920 BST launch, but had to finally admit defeat at midnight.
He added: "Michael Peacock (BBC Two controller) was quite pleased about it because, although BBC Two was known, it wasn't terribly well-known and all the following day's papers had headlines 'BBC Two Fails - Corporation to try again tonight'.
"It was wonderful publicity and made sure people tuned in."
As a result of the disastrous launch, BBC Two's first scheduled programme to go ahead was Playschool at 1100 BST the following day.
Viewers who tuned in to watch the opening night were disappointed
Later that evening, a young Tuohy appeared on screen blowing out a candle in a darkened studio and apologising for the previous night's problems before the opening night's planned schedule was eventually run.
Tuohy said: "We knew we had to make some reference to the blackout so there I was, with my Mod haircut, in the studio blowing out a candle.
"That image is run again and again every time there is a reference to the BBC Two launch, but it was so long ago that most people these days don't have a clue what its all about."
No recording of Priestland's original news bulletin was thought to have been made - that is until February 2003 when a tape was found in a dusty corner of a cupboard in Kingswood Warren, in Surrey.
Engineers James Insell and Stephen Anderson were looking in the modest archive collection when they came across the two inch Quad spool tape marked "Opening of BBC" dated 20 April 1964.
Mr Insell said it was an "astonishing" moment when he realised what it might be and arranged to have the tape transferred to a modern digital format on one of the BBC's only surviving quad VTRs.
The original 1964 recording was rediscovered last year
He told BBC News Online: "We put it on and at first there were a lot of test signals, which was a good sign, and we kept our fingers crossed.
"It was a very exciting moment when Gerald Priestland eventually popped up on the screen."
The recording was made by Alan Bellis - an engineer working at Kingswood Warren on the fateful night
He said the power cut in London had caused some knock-on problems, leading to low frequency and voltage.
A recording of the first night was found last year
"I was running around like someone demented with a screwdriver to get in going and I was so pleased when I managed to record a little bit of it.
"Just then, my manager called me up and said 'you aren't recording this shambles are you?'.
"The next night nobody bothered to record what became the 'proper' opening night - I think we'd had enough by then!"