There are two other household cats: the main antagonist is Blackmalkin, and he is aided by the mysterious Greymalkin who takes his name from the witch's familiar in the opening scene of Shakespeare's Macbeth.

Many maternal characters appear in the book; one takes Kay on a nocturnal ride on a magical horse.

One key recurring theme is the nautical visit of a member of the Harker family to the fictional islands of Santa Barbara.

He is a child among the children in "The Midnight Folk,” which is incomparably the best book of its kind that has appeared since Mrs. Hubert Bland died.

[2]A thread of quiet sarcasm and common sense runs through the amazing narrative., and the marvellous adventures of Kay with the Midnight-Folk will prove entertaining to all adults not blessed, or the reverse, with literal minds.

It was dramatised by Christopher William Hill,[5] produced and directed by Tracey Neale, with music composed by Neil Brand.

It features: Sam Salter, Nickolas Grace, Charles Dance (as Abner Brown), Deborah Findlay, Andrew Sachs, Liz Smith, Helena Breck, Jon Glover, Ewan Bailey, Ann Beach, Harry Myers, Graham Seed, Miranda Keeling, Bethan Walker, Mark Straker, Sam Dale, Ian Masters, Joseph Kloska and Christine Kavanagh.