Doctor Who: The Celestial Toymaker

The travelers arrive in the dangerous domain of the Toymaker, where their failure to win at a series of games could result in them becoming his playthings for eternity. Apparently innocuous nursery characters reveal deadly intent, and for companions Steven and Dodo raise the stakes with every game of the blind man's buff and musical chairs. The Doctor, meanwhile, is rendered invisible and given the challenge of completing the fiendishly difficult Trilogic game.