Theory:Doctor Who television discontinuity and plot holes/Black Orchid


 * The Mackenzie Trent police box, which the Doctor's TARDIS is disguised as did not exist until 1929, four years after the events of this story, yet the policemen recognise it.
 * Police boxes of a similar design had been put into use starting in 1923; police boxes in general had been in use in Britain since 1891.


 * Just how old is Nyssa? She tries to order an alcoholic beverage but the Doctor cuts her off with a loud cough and stops her.