The Lonely Heart

"The Lonely Heart" is the seventh episode of the fifth series of Doctor Who. It first aired on 21st August 2010.

Synopsis
We will be together... forever... and ever. - Elise.

The Doctor, Martha and Kale arrive back in London, where they hear of a new, recreational and completely legal stimulant - 'Ichor', created and endorsed by the enigmatic Elise. But Elise is hiding something, something fatal about her miracle cure, and now they must battle her and the bloodthirsty Nosferox.