Overview: Magnus Magnusson interrogates four more contenders for the title of Mastermind 1991. The black chair is to be found this week in the Academy Room at Stonyhurst College, Preston. Contestants: David Renshaw (civil servant) life and novels of Thomas Hardy; Stephanie Brooke (administrative assistant) life and works of Puccini; Paul Gradwell (credit controller) life and films of W C Fields; Jane Trevor (pre-school day care adviser) life and reign of Richard III.