Big news Doctor Who fans - Michelle Gomez is set to return as Missy in the opening two episodes of series nine.
The announcement about her return was made earlier today.
Steven Moffat, the head writer of the show, said she's coming back because she was an instant hit last year.
Fans will have to watch to find out what brings her back - but we've heard it's the last thing the Doctor would expect.
Doctor Who series nine starts later this year.