Billie Piper will be returning to the Tardis for a sensational last-in-the-series showdown.

The former Ridgeway School pupil, 25, will once again become Rose Tyler for the dramatic episode, joining join fellow former assistants to fight Dalek boss Davros.

The special episode will be screened as the finale to the next series.

Billie starred in 27 episodes of the revived cult show between 2005 and 2006. She first appeared alongside Christopher Eccleston.

Her appearance in the show cemented her transformation from pop star to actress and led to a number of high profile roles.

She is currently starring in ITV2's raunchy Diary Of A Call Girl on Thursday nights and has won critical acclaim for her performance.

The final episode will see Rose and her mum, dad and boyfriend reunite with the Doctor (David Tennant) and current assistant Donna Noble (Catherine Tate).

Freema Agyeman will return as Martha Jones and Elizabeth Sladen as Sarah-Jane Smith.

The Time Lord's robotic dog K-9 will also be making an appearance.