London, Jul 28 (IANS/RIA Novosti): The London 2012 Olympic opening ceremony got off to a spectacular start here Friday, heralding what director Danny Boyle said would be a portrayal of 250 years of British achievements in propelling civilization forward.

The initial stages could have hardly been more British, marked by a flyover from the Red Arrow aerobatics team followed by a 90-second shower.

Boyle, meanwhile, spoke earlier at a news conference that was embargoed until the start of the ceremony because he revealed details of the four-hour, $42 million extravaganza that had until now been kept secret, save for the audiences at two dress rehearsals.

He dedicated the show, first and foremost, to the 15,000 volunteers required to keep the show running.

"Our show, this is the volunteers' show. It absolutely is. They really are the best of us. If you want to judge us as an island, or a series of islands, these people are the best of us."

The show is split into three acts: a "green and pleasant land" theme based on the William Blake poem "Milton" that segues into the industrial revolution; a celebration of Britain's government-funded National Health Service; and a modern-day love story championing British pop music and Internet inventor Tim Berners-Lee.

"We tried to grow something organically, we didn't try to tick any boxes," Boyle said.

He said the fact that he had less than half of Beijing's reported budget in 2008 was a plus.

"You can't get bigger than Beijing, and in a way that kind of liberated us. We thought 'great,' we'll try and use our resources in a different way."