Approximately four minutes of quick-fire specialist and general knowledge questioning confronts four doughty contenders for this year's Mastermind title.Memory, clarity, concentration, tactics, and nerve are all required in this formidable challenge to the intellect.Tonight's contenders are: DENNIS BIRD, Civil ServantJACQUELINE PEARSON , postgraduate studentMICHAEL MUNN , lorry driverMARTIN CABOURN SMITH , Chartered Accountant