We're almost at the end of David Tennant's time as Doctor Who. We've got some clues to how it may all end, but be careful, because there are some big SPOILERS!!!!
If you watched Children in Need you'll know the Ood are back in End Of Time: Part 1, which will be shown at 6pm on BBC1 on Christmas Day.
Some familiar faces are back for the final two specials of David Tennant's turn in the Tardis. Bernard Cribbins returns as Donna's grandad, Wilf - with added antlers.
But it seems he finally gets to step inside the Tardis himself, after keeping Donna's missions with the Doctor secret for so long.
And Donna's back too! Now the last time we saw her Donna's memory had been wiped, so will she get her old thoughts back, and will she be able to cope with them?
Now these guys are definitely new! They are called Rossiter and Addams and seem to be from a race called the Vinvocci. Spiky!
And we've not seen this man before either. He's called Mr Danes and let's be honest, looks like a nasty piece of work.
These people are new too. They're called Joshua and Angela Naismith and we think they look a bit like they could be part of the government or some top secret agency.
But it's not all new stuff. It wouldn't be a Doctor Who episode with the man running around with his coat flying around him.
And it seems the Doctor isn't the only person doing some running in the Christmas episodes. But just who is this mysterious character?
It's the Master! With a funky new blonde haircut! But he's supposed to be dead, isn't he?
It would appear not. And it seems actor John Simm is having a lot of fun bringing back one of the series' top baddies.
So just how will David Tennant leave the Tardis for the last time, and will it be the Master who ends his stint as the Time Lord? We'll find out on New Year's Day in part 2.
Doctor Who and The End of Time Part One will be shown on Christmas Day between 6-7pm. The second part will shown on New Year's Day between 6.40pm - 7.55pm.