In the far future, it is known that humanity will take the stars and forge a stellar empire. But what of the other powers in space that oppose this future?

This week, Paddy and Tricia join The Doctor and Sarah Jane as they find themselves in renaissance Italy when the new age of science is about to emerge. However, something sinister works in the shadows to stop this new age and it intends to make its move at The Masque of Mandragora.