Singer will be joined by Michael Gambon, known to children from the Harry Potter films, in 60-minute special episode

This article is more than 10 years old

This article is more than 10 years old

Welsh singer Katherine Jenkins is to appear in this year's Doctor Who BBC1 Christmas special in her first major acting role.

In what the show's lead writer Steven Moffat told MediaGuardian will be "the most Christmassy Christmas special" since the hit family drama series returned to British TV in 2005, Jenkins will be joined by acting grandee Michael Gambon in the 60-minute special episode.

The 69-year-old Gambon starred as Philip Marlow in Dennis Potter's acclaimed 1980s BBC TV serial The Singing Detective and more recently played the headmaster Albus Dumbledore in the Harry Potter film series.

"Michael Gambon is as distinguished an actor as I can imagine and the fact that he was Dumbledore means that he is already know to millions of children," said Moffat.

He added that he had not known that this was Jenkins's first major acting role before she was cast. "She is brilliant – she is a great singer and a great performer," said Moffat.

Jenkins' acting experience has been limited to a cameo in ITV soap Emmerdale in 2007 in which she played herself opening a fete.

Moffat will be hoping to emulate the success of last year's Christmas specials, at the end of which David Tennant bowed out after four years in the lead role.

Part one of the two-part story, called The End of Time and featuring John Simm and Catherine Tate, was the festive season's third most popular show. Episode one attracted an audience of 10 million, according to overnight figures, with a further 343,000 watching part one on its high-definition channel, BBC HD.

However, this was marginally down on the 11.7 million who watched the 2008 Christmas special, according to overnights, and the 12.2 million who saw 2007's Christmas special, featuring Kylie Minogue as a waitress on the Titanic.

• To contact the MediaGuardian news desk email editor@mediatheguardian.com or phone 020 3353 3857. For all other inquiries please call the main Guardian switchboard on 020 3353 2000.

• If you are writing a comment for publication, please mark clearly "for publication".