Simon Cowell returns (amid an orchestrated PR whirlwind) for the first of the five semi-finals, joining Michael McIntyre, Amanda Holden and David Hasselhoff as the first eight of 40 acts compete to impress the judges and secure the all-important viewers' vote. At stake is the chance to win a cash prize of £100,000 and appear at the Royal Variety Performance. Ant and Dec actually start working for the first time this series, what with them actually having to stand on a stage, as opposed to the side of it, mumbling 'brilliant'. For the half hour where the British public throw away their hard earned money, we're being treated to Corrie, and then the BGT results show follows at 9.30pm.