Doctor Who: 12 Cool Details Russell T Davies Just Revealed About New Earth & Gridlock
4. Newsreader Sally Calypso Came From A 2000AD Comic
Yet another, slightly more sci-fi oriented inspiration for Gridlock was The Ballad of Halo Jones, a 2000AD comic-strip.
As well as being inspired by the 2000AD universe in a general sense, Davies also based newsreader Sally Calypso - who we first meet at the very start of Gridlock - on the character Swifty Frisko from The Ballad of Halo Jones.
In addition, Davies also mentioned that Gridlock was inspired by an episode of British sitcom One Foot in the Grave. More specifically, there's an episode called The Beast in the Cage where main characters the Meldrews are stuck in a traffic jam.
Davies is quite fond of this episode, calling it a "genius" piece of writing.
Seriously... is there any episode of Doctor Who with a more random group of inspirations than this one?