Knockout rounds 1 & 2 - S4.E1

Jayne Middlemiss, Colin Murray, Wendi Peters, Simon Shepherd, Janet Ellis, Deena Payne, Iwan Thomas, Rav Wilding, Pete Waterman, Stephen K. Amos, Gemma Bissix, Shirley Robertson, Ian Bleasdale, Paul Martin, Tracy-Ann Oberman, Brian Moore, Saira Khan, Rosie Boycott, Michael Obiora, Joel Ross, Shobna Gulati, Dennis Taylor, Siân Lloyd, Jan Leeming and Joe Swift. There was also a week of Comeback contestants featuring Joe McGann, Marie Helvin, Linda Barker, Claire Richards, Rowland Rivron, Ninia Benjamin, Steven Pinder, Wendi Peters, Helen Lederer, Tony Hadley, Martin Hancock and Jeff Green