Categories of life

The categories of life was a system used to classify people on Earth after Miracle Day, in which people stopped dying. People were taken to overflow camps with Category Ones being secretly taken to modules and burned alive. Since the formerly immortal Jack Harkness became mortal after Miracle Day, Esther Drummond joked that he was "category Jack". (TW: The Categories of Life)

Categories of life

 * People in overflow camps were given coloured pegs which identified what category they were.