The guest panellists are Emma Bunton and Michael McIntyre. Also premièred is the video for the charity single "Islands in the Stream" released by Ruth Jones and Rob Brydon and featuring Tom Jones.
The guest panellists are Jamelia and Paul O'Grady.
The guest panellists are Lisa Snowdon and Dara Ó Briain.
The guest panellists are Denise van Outen and Michael McIntyre. Ruth Jones, Rob Brydon and Tom Jones perform their charity single "Islands in the Stream" again, Alesha Dixon perform "Let's Get Excited" and the cast of Hairspray perform "You Can't Stop the Beat".
Katie Price, Colin and Justin, Ed Byrne, Rebecca Front and Russell Kane battle it out in front of the judges and for the viewers votes at home for a place in the final.
Penny Smith, Andi Osho, Noel Fielding and Lulu battle it out in front of the judges and for the viewers votes at home for a place in the final.
Joe Swash, Caroline Flack, Toyah Willcox, Clare Grogan, Chesney Hawkes, Limahl, Adrian Edmondson, Marcus Brigstocke and Lee Nelson battle it out in front of the judges and for the viewers votes at home for a place in the final.
All of the finalists return to perform one last time as they battle it out to be crowned the series champions.
Ricky Hatton, Tim Vine and Natalie Cassidy take to the dance floor for Comic Relief.
Jon Culshaw, the cast of Waterloo Road and Antony Cotton tackle iconic dance routines.