Sudoku is a seemingly simple game of placing numbers in empty spaces on a 9×9 grid – but this straightforward game has led to some rather extreme examples of people going all out to play Sudoku. Some people joke about being “Sudoku addicts,” but it’s true – the game can be so incredibly compelling that some people can’t stop playing Sudoku, even when they know that they really should stop.

Sudoku has become one of the most popular puzzle games in the world, and as part of the Sudoku craze a few years ago it was perhaps inevitable that Sudoku would end up on TV. Instead of being confined to a solitary activity of playing Sudoku online or in Sudoku books, Sudoku TV game shows made it possible for people to see Sudoku being played on live TV.

Here are a few of the Sudoku TV game show concepts that have appeared on TV over the years: