The Cybermen launch their deadly megatron bomb which will destroy all life on Earth.
The world’s population is unconscious and the Cybermen invade London in force.
UNIT, Zoe, Jamie and Isobel must confront Cybermen in the sewers beneath London.
The Cybermen are planning to immobilize Earth’s population and Vaughn is helping them.
Trapped by Vaughn’s men, the Doctor requests help from UNIT. But what’s in the cocoon?
The Doctor and Jamie are taken prisoner by Vaughn who denies abducting Zoe and Isobel.
The Brigadier confirms there is something suspicious about International Electromatics.
The TARDIS lands in London and the travelers agree to help find Professor Watkins.