Catherine Tate is heading back to the Tardis as the Doctor's new assistant.
The comedian is set to return to her role as runaway bride Donna, from last year's Christmas special, for the whole of the fourth series.
We last saw her character turning down the Doctor's offer to travel with him, but it looks like she's reconsidered.
She'll be joined by Freema Agyeman, as Martha Jones, halfway though the 13-week run, which is due to hit our screens next spring.
Writer Russell T Davies said he was delighted Catherine was coming back.
"Viewers can expect more ambitious storylines and a whole host of guest stars in 2008," he added.
Earlier this week, TV bosses revealed that pop star Kylie Minogue will star alongside David Tennant in this year's Christmas Day special - Voyage of the Damned.