There's rumours flying that David Tennant is quitting his role as Doctor Who during the fourth series of the time-travelling show.
But the BBC hasn't confirmed or denied the rumours, simply saying that David is "completely committed to the show".
Reports in two newspapers claimed David had told BBC bosses he would be leaving in the middle of series four.
But David said recently that people had been asking him when he was leaving as soon as he joined Doctor Who.
A BBC spokeswoman told Newsround: "The fourth series of the programme has not been commissioned yet so it's absolute speculation and premature to talk about who may or may not appear in the programme.
"What we can say is that David Tennant is totally completely committed to the programme, he's currently filming series three which will air in the spring."
The Doctor will be joined by a new assistant in the third series - Martha Jones, played by Freema Agyeman.