The Doctor and Rose arrive in a quiet suburb of London in 2012, with the residents and council preparing for the Olympic torch to pass through their street in advance of the forthcoming Games. The time travellers soon discover that there have been several local disappearances and the finger of blame is being pointed at anyone nearby.

An old lady has suspicions that a young child may hold the key to the missing persons, although her fellow residents remain sceptical and prefer to blame the council. The girl in question, Chloe, closely observes events from her bedroom window. When a young boy suddenly vanished whilst playing football, she was drawing him at the time with the image suddenly becoming 'animated'. The Doctor pays her a visit and finds out that there has been some domestic upheaval, with her alcholic father mistreating her and her mother.

Pictures drawn by Chloe adorn her bedroom walls and it becomes clear that she is not just lonely, but also disturbed psychologically. Rose snoops around the neighbourhood investigating, but is attacked by a strange ball that resembles a scribble on a page. The Doctor works out that Chloe has the power to effectively take whatever person or object she draws and transport them into the two dimensional picture. Conversely, she can also propel images from her hand into the real world, hence the doodle that attacked Rose.

Events take a sinister turn, as it emerges that Chloe is under the influence of an alien being who is not afraid to trap countless humans within the pictures. Lurking in Chloe's cupboard is a malevolent, paternal force waiting to be unleashed. The Doctor faces a race against time to stop the drawing, save the children and avoid Olympic disaster.