5/8 The Cybermen are planning to immobilise Earth's population and Vaughn is helping them.
4/8 Trapped by Vaughn's men, the Doctor requests help from UNIT. But what's in the cocoon?
3/8 The Doctor and Jamie are taken prisoner by Vaughn who denies abducting Zoe and Isobel.
2/8 The Brigadier confirms there is something suspicious about International Electromatics.
1/8 The TARDIS lands in London and the travellers agree to help find Professor Watkins.