Former teenage popster Piper is to play a character called Rose Tyler in the new version of 'Doctor Who', starring alongside Christopher Eccleston's Doctor in the new 13-part drama series due to return to BBC One early next year.
Winning the role is a real fillip for the 21-year-old Piper, who only made her acting debut last year in the critically acclaimed BBC One drama serial 'Canterbury Tales: The Miller's Tale'.
Julie Gardner, head of drama at BBC Wales, said: "Billie is beautiful, funny and intelligent. We needed to find a unique, dynamic partner for Christopher Eccleston, and Billie fits the bill perfectly.
"She will make an extraordinary Rose Tyler. Doctor Who has his new assistant."
Piper, who also received critical-acclaim for her role in 'Bella and the Boys' a one-off drama for BBC Two, is currently starring opposite 'Lord of the Rings' star Orlando Bloom in Brit flick 'The Calcium Kid'.
"'Doctor Who' is an iconic show and I am absolutely thrilled to be playing the part of Rose Tyler," Piper said.
"I am also looking forward to working with Christopher Eccleston and writer Russell T Davies."
Executive producer and writer Russell T Davies, best known for 'Queer as Folk', said that the Doctor's companion is one of the most important and cherished roles in the history of TV drama.
"I'm delighted that someone of Billie's talent is coming on board the Tardis, to travel through time and space."
The new series of 'Doctor Who' will be filmed in Cardiff later this year and is being written by Davies, Steven Moffat, Mark Gatiss, Paul Cornell and Robert Shearman.
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