Strictly Come Dancing's Oti Mabuse has been teamed with rugby star Ugo Monye in her bid for a third consecutive win.
The professional partners of this year's 15 celebrity contestants were revealed in Saturday's launch show.
Bake Off winner John Whaite will dance with Johannes Radebe in the show's first all-male partnership. Whaite called it "a great step forward".
Comedian Robert Webb will dance with Dianne Buswell, while pop star Tom Fletcher is teamed with Amy Dowden.
This year's launch episode of Strictly was watched by an average of seven million viewers, according to overnight ratings.
It marks a drop in viewing figures from 2020's opening episode which was watched by an average of 8.6 million, while 7.8 million tuned in to watch the contestants meet their partners in 2019.
The cast announcements came after one, unnamed, professional dancer tested positive for Covid last week.
A Strictly spokeswoman told the BBC that the show was following government guidelines, which "change all the time".
"A professional dancer has tested positive for Covid 19. However, this didn't affect recording of the launch show," she said.
All those taking part in the show are being regularly tested and no partners have been swapped as a result of the positive test.
This year's celebrities and their partners
- Olympic swimmer Adam Peaty and Katya Jones
- TV presenter AJ Odudu and Kai Widdrington
- TV presenter Dan Walker and Nadiya Bychkova
- Actor Greg Wise and Karen Hauer
- Celebrity chef John Whaite and Johannes Radebe
- Comedian and TV presenter Judi Love and Graziano di Prima
- Actress Katie McGlynn and Gorka Marquez
- Actress Nina Wadia and Neil Jones
- Actor and children's TV presenter Rhys Stephenson and Nancy Xu
- Comedian and author Robert Webb and Dianne Buswell
- Actress Rose Ayling-Ellis and Giovanni Pernice
- Entrepreneur and TV "Dragon" Sara Davies and Aljaž Škorjanec
- Social media star and children's TV presenter Tilly Ramsey and Nikita Kuzmin
- Pop star and children's author Tom Fletcher and Amy Dowden
- England Rugby star Ugo Monye and Oti Mabuse
Saturday's launch programme was pre-recorded a week ago, with the positive case discovered the next day. The first live show takes place on 25 September, leaving sufficient time for self-isolation in between.
The spokeswoman refused to comment on reports in Saturday's Sun that two of the show's professional dancers had refused to be vaccinated.
"We do not comment on speculation of somebody's Covid vaccination status," she said
"Strictly Come Dancing production has, and will, continue to follow strict government guidelines to ensure the safety of all on the show."
Hosts Claudia Winkelman and Tess Daly kicked off proceedings in Saturday's pre-recorded show, which featured returning judges Shirley Ballas, Craig Revel Horwood and Motsi Mabuse and new arrival Anton Du Beke.
Du Beke, the show's long-serving professional dancer, replaces Bruno Tonioli on the judging panel after Tonioli, who lives in the US and is a judge on American series Dancing With The Stars, was unable to take part because of ongoing Covid travel restrictions.
Reigning champion Bill Bailey also returned to perform with his former professional partner Oti Mabuse. Bailey, who was 55 when he won, became the oldest celebrity to lift the glitterball. Actor Greg Wise, partnered with Karen Hauer in this series, is also 55.
Mabuse is the only professional dancer to have won two years in a row, following her triumph with Emmerdale's Kelvin Fletcher in 2019.
Former Strictly dancer Aliona Vilani is the only other person to have two of the show's winning glitterballs, dancing to victory with McFly's Harry Judd in 2011 and, four years later with The Wanted's Jay McGuinness.
Monye - Mabuse's partner for the 19th series - revealed he would be simultaneously filming nine episodes of A Question of Sport during the second week of Strictly.
"I've got some big shoes to fill," said Monye, but he added: "She definitely knows how to win."
Celebrity chef John Whaite and South African pro dancer Johannes Radebe follow in the footsteps of boxer Nicola Adams and dancer Katya Jones, who became the first same-sex pairing last year.
Whaite told Daly he had been surprised and delighted by the positive reaction to his same sex pairing with Radebe adding that he had been "expecting a little hate, a bit of trolling".
He said it was a "a privilege and an honour to be in this position because I think if I had seen two lads or lasses in this position when I was a little lad, life would have been that little bit easier".
Two years ago, Radebe - who has been one of the professionals on the programme since 2018 - said he felt accepted for the first time in his life after he made history on the show by dancing with another man, out of competition.
He and fellow professional Graziano di Prima performed together to Emeli Sande's Shine on one of the Strictly results shows.
This time around di Prima will partner Loose Women panellist Judi Love.
The show's first deaf contestant, Rose Ayling-Ellis, who will dance with Giovanni Pernice, said the response from the deaf community to her appearance on Strictly had been "her proudest moment".
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