We got unbelievably lucky with Jacob Dudman. This story working to the extent that it does relies on an actor who is not just talented in the craft of acting, but also able to capture the voice of others. I had no problem being swept up by his authoritative and authentic take(s) on The Doctor.

Alfie Shaw manages to overcome the multi-Doctor story limitations and squeezes an interesting plot into proceedings. We get lots of exciting dialogue between the two Doctors but it all serves a purpose and drives a story - which isn’t always a given once you have more than one time lord in the same room.