Nicola Bryant

The Doctor and Peri meet Jamie and learn the Second Doctor is with the Sontarans in Spain on Earth. At a Hacianda, Chessene and the Sontarans set up base.

Chessene and Shockeye succumb to their baser instincts and revert to their Androgum ways, while the Sontarans prepare the Second Doctor to trigger their Kartz-Reimer capsule.

As Peri and Areta begin to transform into a bird and a reptile, the Doctor faces Sil, who has negotiated mining rights on Varos, depriving the Time Lord of what he needs...

Mestor claims that all he wants is for the Sylvest twins to help him repopulate his home planet but the Doctor knows there's more to this than meets the eye.

On Jaconda, Mestor's cruel domination over the planet's population continues while on Titan Three, the Doctor seems to have been blown up in a booby-trapped building.

On Telos the Doctor is reintroduced to the Cyber Leader and meets the Cryons, the planet's original inhabitants who want their planet back and will go to any lengths to do so.