Here is the newsround review of the second episode which sounds great:
The Doctor and Donna accidentally land in the ancient Roman city of Pompeii. And their timing couldn't have been worse.
It's the day before a huge volcano is due to erupt and bury the city killing everybody there.
The Doctor just wants to leave, but Donna thinks he should try and save the city. And that's when things take an even more mysterious turn.
People living in Pompeii are talking about a prophecy involving a blue box, and some even seem to know exactly who The Doctor and Donna are.
This is an episode that's everything an episode of Doctor Who should be.
The Doctor and Donna have a huge row!
Each of them is convinced they're doing the right thing.
That alone would make this a standout episode, but there are also some of the best special effects yet seen on the show.
As well as a few more tantalising hints about what might be coming later in the series.
All in all, one of the very best episodes the show has produced.
Five out of five.