Barry Letts’ last novel, published in 2005 just after New Who began, but taking the Third Doctor, Sarah Jane Smith and the Brigadier to investigate a strange cult based around a mind-altering drug and rescuing Sarah’s gormless assistant Jeremy (from The Paradise of Death and The Ghosts of N-Space). It’s not great, to be honest; the story rambles and characters make rather arbitrarily stupid decisions in order to prolong the plot. But we should take it as what it is, a farewell note to the series from one of its veteran producers.