The play — like Her Majesty — was celebrating 50 years of non-stop performance, and the audience was made up of past cast members and their guests.
The evening began with the National Anthem being played before the curtain rose, and the traditional curtain-call speech, in which the audience are asked to keep The Mousetrap's secret "locked in your hearts." The speech was given by Lord Attenborough.
As plain Richard Attenborough he (and his wife Sheila Sim) had been in the original cast when it opened at the Ambassadors Theatre in London Nov. 25, 1952.
Lord Attenborough famously cries at the drop of a hat, but for once tears were in order, and there wasn't a dry eye in the house as he and Lady Attenborough appeared on stage to give the speech.
Another speech was by Sir Stephen Waley-Cohen, the current producer of The Mousetrap, who paid tribute to the original producer, Sir Peter Saunders. Sir Peter was unwell and unable to attend, but his wife (Katie Boyle) was in the audience.
The Queen was applauded as she left, but there was one more surprise left in store — after she had left her place in the front row of the Dress Circle, the curtain rose again to reveal the Queen on the stage, greeting the members of the current cast.
Given her mother's longevity, it's entirely possible that the Queen will be back to celebrate The Mousetrap's 75th birthday in 2028.
— By Paul Webb Theatrenow