A chaotic mess of violence with cartoonishly nasty creeps getting their due
The action is solid, but the level of damage one guy can inflict on whole groups of armed opponents does border on ridiculous even choreographed well-enough, especially the last one on one fight

A brilliant official introduction to the 15th Doctor

The Doctor's newest challenges seem to be based on dealing with unusual threats than usual
Ruby is a brilliant companion, and there are plenty of interesting twists that promise the upcoming season will be a wild adventure

8 out of 10
Great dynamic between Ruby and 15, especially the family bonds. The threat could have been more developed to explain how they function and how they were defeated. But the devastation of a life lost and all it costs was brilliantly handled.
Ncuti was brilliant, he will make an incredible Doctor for the adventures ahead.

This is legitimately a terrifying episode, possibly one of the strongest in years.

The Doctor and Donna are turned into the greatest threat to their very existence.

Once it's fully pieced together the personal devastation both suffer is quite impressive.

Their trust in each other tested and connection, the Doctor's most treasured link to reality, violated. (Tennant is brilliant in a brief moment of showing how utterly shattered to the core the 14th Doctor was)

Best special so far, with a beautiful moment at the end....

As the Anniversary special enters it's final arc...
The final adventure of the 14th Doctor is near