"Attack of the Graske" is an interactive mini-episode of the British science fiction television series Doctor Who that was first broadcast on the BBC Red Button service on 25 December 2005.
By alternating between two different viewpoints, namely from within the family's television set and from the handheld digicam the daughter got for Christmas, the viewer has to determine who does not belong.
As the Doctor tracks the Graske through time, the viewer takes command of the TARDIS's controls, and activates the vortex loop, dimensional stabiliser, and vector tracker as requested.
The viewer must use a map on the TARDIS scanner to pinpoint its location, as the screen blips where the Graske's DNA is found.
Having used three number and logic puzzles to pass through the airlocks, the viewer arrives in a room filled with various beings in stasis pods; the Graske keep the originals to sustain the copies.
The viewer also learns of the Graske's ultimate intention to replace every living, sentient creature in the universe with one of their doubles.
The blast ricochets around the room and frees a Slitheen from a stasis pod, who then proceeds to vengefully chase the Graske who imprisoned it.
[1] Executive producer Julie Gardner told Doctor Who Magazine that the mini-episode was treated as a "full-blooded, sophisticated production," with a new alien villain, new sets and new special effects.