Keep it a secret! Opening Ceremony rehearsal audience told

Over 60,000 lucky people who were given a sneak preview of the Opening Ceremony at the Olympic stadium here have been sworn to secrecy by the organisers.

Around 62,000 people were lucky enough yesterday to watch a dress rehearsal of the Danny Boyle directed 27 million pounds extravagant Opening Ceremony that will spark London 2012 to life.

Fans invited to the sneak preview in the Olympic Stadium in Stratford, east London, were urged personally by the Slumdog Millionaire director to 'save the surprise' for the one billion around the world who will watch on Friday night.

Organisers invited London 2012 volunteers, competition winners and others connected to the Games on the proviso that they kept quiet about what they saw, the Daily Mail reported.

The ceremony's artistic director Danny Boyle addressed the huge crowd and called on them to reveal nothing ahead of Friday's showpiece by not posting any images on social networks.

The hashtag #savethesurprise was also emblazoned on giant screens inside the Olympic Stadium, according to people at the event, before trending globally on twitter.

It is already common knowledge that the stadium has been transformed into a British rural idyll. The stadium will be packed with at least 62,000 spectators, 16,000 athletes, 10,000 performers, 70 sheep, 12 horses, ten chickens, three cows, two goats and even dogs and geese.

Traditional countryside cottages will stand together with a mining wheel, harking back to the country's proud industrial heritage, all drenched in faked pouring rain to reflect Britain's typical weather.

And mimicking scenes across the country every weekend, a cricket pitch has even been laid with a game planned for during the ceremony.

But in the main the contents of the three hour multi-million pound extravaganza is still a complete mystery.

Movie director Boyle and his creative team have done their best to keep details of the opening ceremony secret and it seemed that most spectators at last night's rehearsal followed their wishes by not revealing any of the shows big surprises.