“London 2012: Time to find out who we are” reads a headline in today’s Guardian. I’m not so sure about that, but the world will find out tonight what Danny Boyle’s had up his sleeve during his long months of preparing the Olympics Opening Ceremony. A shroud of secrecy has hung around the build-up to the event and around two dress rehearsals Boyle held earlier this week. What did leak was news that the hashtag #SaveTheSurprise had been projected on screens around the stadium during the rehearsals. Seems to have worked.

What we also know is that the warm-up show will start in London at 8:12 local time tonight (20:12 in military time), kicking off in earnest at 9 PM and running to 12:30 AM. Folks in the U.S. will have to wait until several hours later since NBC made the decision to slot the opening and closing ceremonies in primetime. Yesterday, NBC Olympics executive producer Jim Bell praised Boyle’s extravaganza, saying it has “amazing moments including one of the more astonishing and memorable in opening ceremony history.”

Related: London Olympics Preview: Coverage Is “Hybrid Of Innovation And Tradition”, But Will It Do The Job?

The $43M show, Isles Of Wonder, named for Caliban’s speech in Shakespeare’s The Tempest, is a tribute to Britain through the ages. Boyle has said it “salutes and celebrates the exuberant creativity of the British genius in an Opening Ceremony that we hope will be as unpredictable and inventive as the British people.” About 15,000 actors are taking part along with 12 horses, 3 cows, 2 goats, 10 chickens, 10 ducks, 9 geese, 70 sheep, and 3 sheep dogs who’ll romp on the Olympic Stadium version of the British countryside. There will be 12,956 props and 23,000 costumes including those for the nurses that Boyle has said will feature in a dance number. Music from the opening and closing ceremonies will be made immediately available online after the events. Apart from the show, there will be the requisite parade of nations with athletes from the 204 competing countries, various speeches and the lighting of the Olympic Cauldron. Heads of state, dignitaries and celebrities in attendance are expected to include Queen Elizabeth II, Prime Minister David Cameron, German Chancellor Angela Merkel, Russian Prime Minister Dmitry Medvedev, US First Lady Michelle Obama, Princes Harry and William and William’s wife the Duchess of Cambridge, David Beckham, Helen Mirren, Brad Pitt, Angelina Jolie and Judi Dench.

The scuttlebutt around London also points to a possible appearance by Dench’s James Bond co-star Daniel Craig in a prepared sequence as well as Kenneth Branagh reading the Caliban speech in the place of Mark Rylance, who had to back out a few weeks ago. There’s also talk of a 40-foot tall Voldemort, 30 Mary Poppinses wafting through the air, inflatable puppets of Cruella de Vil and Captain Hook, a Beatles tribute, and Paul McCartney performing Hey Jude to close out the evening.