Gridlock

Episode Title:
Gridlock

Written By:
Russel T Davies

Starring:
David Tennant - Doctor
Fremma Agyeman - Martha Jones

Alien:
Macra, Sister of Plenitude and Face Of Boe

Air Date:
14th April 2007

Synopsis:
The Doctor takes Martha to the planet New Earth, in the far future, as the third series of Russell T Davies' Doctor Who continues. But when they find the streets being ruled by the sinister Pharmacists, they must brave the ordeal of the mysterious Motorway in order to discover the terrible secret at the heart of the city.