The Doctor and Sarah Jane Smith arrive on a remote planet only to discover that their presence is somehow manifesting the crew's deepest fears into reality. The TARDIS lands on the jungle planet of Deva Loka, a world that seems to be a paradise, but soon the Doctor and Sarah Jane realize that the planet itself is alive and feeding on the negative emotions of the human colonists. As the colonists' fears begin to take physical form, threatening the Doctor and Sarah Jane, they must find a way to overcome the planet's psychic influence before it consumes them all. The narrative unfolds through a traditional linear progression, focusing on the unfolding mystery and the escalating danger.

As a novelization of a classic Doctor Who serial, 'Planet of Evil' offers fans a chance to revisit a beloved story in a different format. The book is likely to be appreciated for its faithful adaptation of the television plot and its exploration of the Doctor's character. Readers familiar with Terrance Dicks's work will recognize his characteristic style of adapting Doctor Who stories for the printed page. The story itself is known for its psychological horror elements and its challenging themes, which are well-suited to the novel format.