It’s play time on Start the Week. The mathematician Marcus Du Sautoy looks at the numbers behind the games we play, from Monopoly to rock paper scissors. In Around The World in 80 Games he shows how understanding maths can give you the edge, and why games are integral to human psychology and culture. The historian Anthony Bale looks at game-playing in the medieval world. In A Travel Guide to the Middle Ages, he finds travellers passing the time with dice and tric trac, as well as collecting pilgrim badges along the way. Many of today’s most popular video games immerse players in historical settings, and the practice of collecting items along the way is nothing new to gamers. The co-director of the Games and Gaming Lab at the University of Glasgow, Jane Draycott, researches the historical authenticity of these online worlds, and especially the depiction of women. And the mathematician G.T. Karber has taken his love of classic detective fiction and puzzles to create the murder-mystery riddle Murdle. A combination of Cluedo and Sudoku, what started as an online game is now a series of bestselling books. The latest is Murdle: More Killer Puzzles. Producer: Katy Hickman