Age vs beauty: The reality TV game

Alesha Dixon, 30

Also known as: The British Beyonce, according to Strictly host Bruce Forsyth

Dancing skills: Dixon learnt street dancing as a child.

Contribution to pop: As part of the girl group Mis-Teeq, gave the world seminal works such as "Scandalous" and "One Night Stand".

Education: Had a place at Loughborough University, but gave it up to be a star.

Big break: Was approached by a record producer on a train. Note to kids: don't try this at home.

The face of: JD Sports, Ford Focus, Veet and the Department of Health's safe sex campaign.

World records: In May she broke the Guinness World Record for performing with the most choreographed backing dancers: 329.

Mountains climbed: Kilimanjaro for Comic Relief earlier this year.

Heartbreak: In 2006 Dixon and her husband, MC Harvey from So Solid Crew, separated after he had an affair with the singer Javine Hilton.

Sex appeal: Dixon dancing in a little swishy skirt was the only reason any straight men watched Strictly.

Arlene Phillips, 66

Also known as: She who must be obeyed.

Dancing skills: Began ballet classes at three. Has choreographed some of the most successful West End shows.

Contribution to pop: Choreographed the Seventies and Eighties dance sensations Hot Gossip.

Education: Phillips is a leader, not a follower: in the early 1980s her two LPs, KISS (the Keep in Shape System), entered the UK album chart.

Big break: After moving to London, she was asked to choreograph a commercial for Lyon's Maid ice-cream.

The face of: The British Empire – was made an OBE in 2001 for getting the nation dancing

World records: Not officially, but is probably planning one involving young male dancers and their bottoms.

Mountains climbed: Not literally, but she did choreograph The Sound of Music in 2006, starring Connie Fisher.

Heartbreak: Yes, but mostly as the cause rather than the recipient among her young dance students

Marital status: Arlene and her husband, 49-year-old Angus Ion have been together for more than 20 years.

Sex appeal: For the sort of person who has finally accepted it's no longer OK to have a crush on Margaret Thatcher.