The entire show is a delusion by which the inmates of an oppressive prison cope with their incarceration.
Locked into a crimethink gulag, their every thought, step and action are controlled by the nigh-omniscient surveillance loudspeakers which tell them everything they must do such as watch "educational" propaganda films, exercise in the yard, or eat the disgusting rations of nutritional paste that is, "Tubby Custard" or waferlike "Tubby Toast." Any attempt to hide from the surveillance causes an immediate alert "Where have all the Teletubbies gone?" Is it any wonder the prisoners have covered all of this by replacing it in their minds with a sunny, bucolic landscape of bright cheerful colors, even unto the all-seeing infant "sun"?