The principal characters who lead us through that world are ordinary human beings like ourselves: Winston Smith and Julia, whose falling in love is also an act of rebellion against the Party. Opposing them are the massed powers of the state, which watches its citizens on all sides through technology now only too familiar to us. No-one is free from surveillance; the past is constantly altered, so that there is no truth except the most recent version; and Big Brother, both loved and feared, controls all.

Even the simple act of keeping a diary – as Winston does – is punishable by death. In Winston’s battle to keep his freedom of thought, he has a powerful adversary in O’Brien, who uses fear and pain to enter his very thought processes.

Does 2 2 = 4? Or is it 5? We find out in Room 101.