Good morning.

Today, a snowbound guesthouse on a London stage… and the ending its audiences have kept secret for over seventy years.

Let’s begin.

The Play That Never Ends

Agatha Christie—The Mousetrap

The author is Agatha Christie, already the most famous crime writer in Britain. Even she does not expect much. In her autobiography, she later recalled guessing it might run for eight months.

The play had begun life five years earlier as a much smaller thing. In 1947, the BBC asked Christie for a radio play to mark the 80th birthday of Queen Mary, the widow of King George V. She wrote a twenty-minute mystery called Three Blind Mice, broadcast on 30 May 1947.

Then she expanded it for the stage, with more characters and a fuller plot. But another play called Three Blind Mice had already run in London, so it needed a new name.

The answer came from Shakespeare. In Hamlet, the prince hires travelling actors to stage a murder in front of his uncle, to see if the king flinches. He calls the play “The Mousetrap.” This is that scene, as the Irish-born painter Daniel Maclise imagined it in 1842.

Daniel Maclise, “The Play Scene in ‘Hamlet’,” 1842. Tate, London. Public domain.

Find Hamlet first. He lies on the floor at Ophelia’s feet, watching his uncle’s face rather than the actors. Then find the king, Claudius, recoiling as his own crime is played out in front of the whole court.

Christie’s story is simpler, and set in her own century. A snowstorm traps a group of strangers in a country guesthouse called Monkswell Manor. The radio brings news of a murder in London. And one of the guests is a killer.

It ran at the Ambassadors for more than twenty-one years. Then, in March 1974, it moved next door to the St Martin’s Theatre, where it still plays tonight. This is its home.

The Mousetrap at St Martin’s Theatre, West Street, London, 2006. Public domain.

The St Martin’s opened in 1916 and seats about 550 people. It is a small house for a giant record.

By 1957, The Mousetrap was already the longest-running straight play in the West End, and the playwright Noël Coward sent Christie a telegram of congratulations. On 12 April 1958, it became the longest-running play in the world. It has held the title ever since.

The numbers keep climbing. By 2022, about ten million people had seen it in London. On 19 March 2025, it gave its 30,000th performance.

Only one thing has ever stopped it. On 16 March 2020, the COVID-19 pandemic closed every theatre in London. The Mousetrap reopened on 17 May 2021, and it is now booking into the summer of 2027.

Every year the cast changes, so hundreds of actors have played these parts. Yet the play itself never changes… and neither does its strangest tradition.

At the end of every performance, the audience is asked not to reveal who did it. In other words, millions of strangers have kept the same secret, on their honour, for more than seventy years.

Here is Christie herself in 1950, two years before the first night, with her second husband, the archaeologist Max Mallowan.

Agatha Christie and Max Mallowan at their home, Winterbrook House, 1950. Photographer unknown. National Portrait Gallery, London.

She made one more unusual decision. Before the play opened, she gave the rights to her grandson, Mathew Prichard, as a present for his ninth birthday. She had no idea what she was giving away.

And in 1956, the producer Peter Saunders sold the film rights with a shrewd condition. No film could be released until six months after the London run ends. So there has never been a film.

The first time I saw it, I was in London for meetings and had one free evening. I was sure I had solved it by the interval. Of course, I had not. Afterwards I walked out into West Street with a dozen strangers, all of us grinning, and none of us saying a word.

For a glimpse behind the scenes, the Victoria and Albert Museum holds the original prompt book, covered in the stage managers’ doodles of mice: 65 Years of The Mousetrap →

Christie guessed eight months. Seventy-three years later, the curtain still rises… and the secret is still safe.

Three Things Worth Knowing

Curious & Controversial

Connoisseur’s Diary

Worth Seeing This Week

You can still take your seat in the world’s longest-running play, in the same small theatre it has filled since 1974. Go with a friend, argue about it at the interval, and keep the secret afterwards.

Where: St Martin’s Theatre, West Street, London WC2H 9NZ, near Leicester Square station.  Tickets: prices vary by date and seat; now booking into July 2027.  Insider tip: Midweek performances, Tuesday to Thursday, are usually the best value. And the seats are old and snug, so ask for an aisle if you are tall.  The Mousetrap at agathachristie.com →

Worth Reading

An Autobiography — Agatha Christie (1977). Published after her death, it is warm, funny and surprisingly modest, with her own account of how The Mousetrap began.

Explore Further

Browse: The official Mousetrap page →, the history of the play from the Christie estate.

Read: 65 Years of The Mousetrap →, the V&A on the original prompt book and the play’s odd history.

Tonight’s Quiz

1. What was The Mousetrap called when it began as a radio play in 1947?

A) Monkswell Manor

B) Three Blind Mice

C) The Hollow

D) A Murder Is Announced

2. Who did Christie give the rights to the play?

A) Her daughter

B) Her publisher

C) Her grandson

D) The BBC

3. Where was Christie found after her disappearance in 1926?

A) Brighton

B) A hotel in Harrogate

C) Her sister’s house in Torquay

D) A ship to New York

If the links above don’t respond in your email app, just reply with your answers—I’ll write back.

Most plays want to be talked about. This one has lasted more than seventy years by asking its audience not to. That may be the cleverest trick Christie ever pulled.

Tomorrow, a poem that made its author famous almost overnight in 1845… and reportedly earned him about nine dollars.

In good taste,
Charles T. Mayfair

Editor, Connoisseur Daily