Moment From Doctor Who S04:E08

The First Regeneration
After The Doctor, Ben, and Polly have defeated the Cybermen, The Doctor is feeling unwell. Is it over for The Doctor or is it far from being all over?
The Cybermen take over the base again, apparently to stop the humans using the Z-Bomb, but then the Doctor realises they intend to use it themselves to destroy Earth.
Tags: BBC One, time travel, alien, space, time traveler, tardis