Gridlock (Doctor Who)
"Gridlock" is the third episode of the third series of the British science fiction television series Doctor Who, first broadcast on BBC One on 14 April 2007. It was written by Russell T Davies and directed by Richard Clark.
In the episode, alien time traveller the Doctor (David Tennant) takes his new companion Martha Jones (Freema Agyeman) to New New York in the far future, where they discover the remainder of humanity on the planet live in perpetual gridlock within the Motorway, an underground highway system.
"Gridlock" completes a loose trilogy that began with "The End of the World" (2005) and "New Earth" (2006). It was viewed by 8.41 million viewers in the UK.
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