Your ship is at the bottom of the English Channel, your crew are probably dead, and your nearest source of food is in a Loch six hundred miles away. And the natives are insane. Life isn't looking too promising for a Zygon called Bobby. Victorian London is not a great place to be if you're a wounded shape-shifting alien.
The Great Space Elevator is a marvel of human engineering, a transit tube stretching from the equator up to a space station held in geosynchronous orbit. When the TARDIS lands in Sumatra in the future, the Second Doctor, Jamie and Victoria are captured by guards just as the station loses power. Together with Security Officer Tara Kerley, the three travellers take a one-way trip on the elevator to fix the problem and find themselves confronted by a powerful alien force that threatens to wreak chaos on Earth.
Deborah Watling is best known for her role as Victoria in Doctor Who, alongside the second Doctor, Patrick Troughton. But many people aren't aware of her extensive acting career on stage, film, and television. Born into a theatrical family, her first on-screen roles were as a child in William Tell and episodes of The Invisible Man. But it was her role as Alice in The Life of Lewis Carroll that brought her to the attention of Doctor Who producer Innes Lloyd.