Dreams of Empire by Justin Richards

In Dreams of Empire the Doctor and his companions land in what seems to be a medieval castle, the Doctor and his companions find that the final act of a drama that has ripped apart a the once proud Haddron Empire is being played out around them.

Who is the man behind the mask, and how are his chess games linked to life and death in his fortress prison? What is the secret of the suits of armour which line the banqueting hall? Who is on the battle cruiser that is getting closer all the time, and what will they want when they finally arrive?

The pieces are all in place, and the TARDIS crew soon find themselves under siege. With both deadly robot troops and human traitors to defeat, it seems the future of the entire empire hangs in the balance..