Overview: A life-long mercenary commander and weapons expert is commissioned to train an army for an exiled African leader. But as his conscience finally catches up to him, he is seen as a threat to the powers behind the operation.
Overview: The Doctor, Jamie and Zoe return to Earth and become embroiled in the schemes of Tobias Vaughn. They meet up with an old friend, Colonel (now Brigadier) Lethbridge-Stewart, and some old enemies, the Cybermen.