With Magnus Magnusson. St Andrews University, Scotland's oldest, is the setting for tonight's heat of Mastermind, when four contenders, all living in Scotland, compete for a place in the semi-finals. Hamish Cameron (computer manager), whose specialist subject is the Stewart kingdom of Scotland, 1371-1603; Lydia Skinner (principal teacher) - the lives and writings of Somerville and Ross; David Smith (consultant surgeon) - the life and missionary journeys of the Apostle Paul; David Henderson (part-time college lecturer) - the Para Handy tales and Glasgow stories of Neil Munro.