Katy joins JLS, who will be entertaining the audience with a special performance of their Sport Relief single Proud, while eight finalists pull out all the stops in a bid to be crowned the Let’s Dance Champion for Sport Relief 2012.

Alex Jones and Steve Jones host the live final, as viewers vote for who they want to win the coveted twinkle-toed champion of the dance floor title. Over the past four weeks, 20 celebrity acts have been performing iconic dance routines, from Tina Turner’s Proud Mary to Lady GaGa & Beyoncé’s Telephone, in a bid to impress the judges and viewers, and win a place in the final.

This week the finalists will have to go all out to wow the viewers as the winner will be crowned based on the viewers’ phone votes alone. The panel of Paddy McGuinness, Rhod Gilbert and Frank Skinner will be on hand to offer their opinions on all of the performances.

Last year Emmerdale’s James Thornton and comedian Charlie Baker stole the show with their unforgettable Putting on the Ritz tap routine - but who will dance their way to victory and take the crown this year?

Let's Dance For Sport Relief is simulcast on BBC One and BBC One HD.