Games get serious at ninth Sudoku world championships in Britain
Record numbers from around the world descend on a UK pub for a puzzling event
In an ornately decorated conference room in Croydon, South London, 180 heads are bowed.
"Everyone's got a script?" the supervisor asks. "You may begin now."
As booklets are turned over and concentrated silence fills the room, interrupted only by the frantic scratching of pencils, it becomes clear that sudoku is a solemn business.
This is the ninth world sudoku championships, this year being held in Britain for the first time.
Teams of four from 34 countries, from China and South Korea to Greece and the United States, have travelled to a suburban hotel in Surrey to compete for the glory of the title of world sudoku champion. The international craze for the Japanese puzzle was sparked by Wayne Gould, a retired Hong Kong judge.
Over two days the competitors will take part in 11 rounds of 45-minutes, grappling with over 60 different varieties with names such as killer sudoku, thermo sudoku and sandwich Sudoku.