There's an old story about an American tourist in London who, during his trip, gets picked up by a black cab driver, dropped at his destination, but doesn't tip. Later the same day, he gets picked up again by the same driver, taken across the river, but again fails to tip. Finally, that evening, he gets picked up one last time. "Where are we going?" says the driver, grumpily. "I have tickets to see The Mousetrap," replies the arrogant tourist. They trundle through theatreland, arrive at St Martin's Theatre, where the play is showing, and the American gets out. The cab driver, furious at this point for still not receiving a tip, tells his passenger the name of the murderer.
So, if you're going to see The Mousetrap at the White Rock Theatre (27 Nov - 2 Dec) and taking a cab to get there, make sure you tip your driver.