Episode 4 - Sneak Peek 2

Inside the cave, The Doctor aims his sonic screwdriver using it as a torch, The Doctor then slips and he falls down a small dirt path inside the cave and lands inside a huge room inside the cave.

The Doctor walks over to a machine that has a newly designed Cyberman inside, reminiscent to the Invasion Cybermen, but modernised. The Doctor goes "oh you've come to wake up an army".