Fraser James is very good as Marek and has come on quite a lot since the last series. He is more central to the storyline than he had been in previous stories because we get a bit of back story to him and learn what his dad was like. I also found Ciara Janson and Laura Doddington to also be on good form. It seems that they as well as Simon Guerrier seem to have got a hold of the characters and as a result the story felt more structured than the previous series and that’s why I thought that this story was better than ‘The Sphere’.
The point where Abbey and Zara start to transport the inhabitants from place to place is the prime example of why the Doctor is an important part of a sci-fi. As they were suppose to die the Doctor wouldnt change history yet Abbey and Zara do it with reckless ease. Their determination to do good would obviously have knock on effects and we have the most obvious result. Both Marek and Joy disappeared moments later. I do find it odd that neither Abbey or Zara didnt twig this would happen. Did they never go to Timeline 101 at school? This persumably gets rid of the baby which would have proved a heavy weight around the neck of the series, however this may be a red herring with two more stories in the series to go.
I liked this story as it was like the first series but seemed better structure wise and as a result was a better start to the series than the first and I have high hopes for the other two adventures.