Previous book: Beasts of Olympus (Series, Book 2): Hound of Hades.

Next book: Beasts of Olympus (Series, Book 4): Dragon Healer. 

This is the third book in the "Beasts of Olympus" series. Pandemonius (or Demon as he is most commonly refer to in the series) is the 11-year-old half-mortal son of the god Pan and the mortal Carys. Demon is the official beast keeper of the Olympic gods and it is his responsibility to take care of the various beasts. In this story, Demon is visited by Poseidon, who orders him to accompany him to his realm and check on his sick hippocamps. Demon is frightened to leave the stables at Olympus (he is worried that no one will take good care of the beasts wile he is away and they might cause trouble to the gods), but Arnie the Griffin promises him that he can take care of the animals for a while. Demon then goes with Poseidon, who provides him with his own power so that Demon can breathe underwater. In Poseidon's stables, Demon discovers that the hippocamps suffer from a serious itch which causes their scales to come off. Using Hephaestus' magical medicine-box he is able to cure them. While in the stables of the ocean, Demons is visited by Eunice the Nereid, the daughter of the Old Man of the Sea (Nereus). Slowly they become friends and she confides in Demon that she really wants to be the keeper of the horses. She is bored with her 49 sisters who are always discussing jewels and she does not like attending Queen Amphitrite. Later, the queen asks Demon to her quarters since she wants to hear the new gossip from Olympus.

While Demon believes his job is finished, he is suddenly caught between a vocal argument between Poseidon and Helios. Each believes his horses are faster and they agree to race each other. Poseidon then orders Demon to remain with him for another week. (Luckily for the worried Demon, Hermes helps him find a replacement at the stables on Olympus until he returns.)

Demon travels with Poseidon and his entourage to his second palace on the island of Macris. There Helios approaches him and asks him to take care of his horse, Abraxas, that has cut his leg on a star. Helios then orders Demon to make his horses race faster than Poseidon's or face serious punishment. Demon is scared but is not willing to harm the hippocamps. Helios' horses listen to Demon's problem and together they devise a plan. Demon will receive a special herb from the old man of the sea which causes animals to run fast. He will apply it to Helios' horses but secretly to the hippocamps as well. That way Helios will be pleased that his horses run faster and the race will remain fair. Eunice learns of this plan and helps Demon get the special swiftness juice made form the special herb.

The day of the race arrives and both teams run equally fast, because of the secret juice. In the end they both cross the finish line together, hence everyone is happy. During the ceremony, Poseidon asks Demon how to reward him. Demon asks that Eunice will be the guardian of the hippocamps and Poseidon gladly agrees.

At the end of the book there is a glossary with a short description of the different beasts, gods and goddesses, mythical beings and places which are presented in the stories.

Black and white cartoonish drawings appear at the end of some chapters and some of them appear in numerous books. They show a scene (for example Hades and Demon) or an individual beast.

This installment is lighter in tone that the previous volume on Hades, and focuses on the race as well as on Demon's moral dilemma. The ecological message is emphasized clearly here. Demon is unwilling to hurt any beast, even if it may cost him his life. The horses themselves also stand against injustice and help Demon manipulate Helios.

This story also reveals the unkind nature of the gods. They are all-powerful and can be unpleasant and even immoral. Demon is afraid of both Poseidon and Helios and he is tired of their threats. "'I'm fed up with gods pushing me around and bullying me.'" [location 720].

Demon thinks that Poseidon is nicer than Hera and Hades, yet he is still afraid of him.

Zeus is described as fair and as someone who hates cheating. Since he is the judge in the race, the horses calm Demon's worries that Helios might punish him if he does not obey him.

In this story Demon meets a new girl and the author gently approaches boys-girls relationships. Eunice is not interested in "girly" things, as they are presented here. She does not wish to discuss clothes or jewellery and prefers being in the stable. She hates traditional girls' roles, i.e. a nymph-in-waiting for queen Amphitrite. Demon is also embarrassed by Eunice' sisters, who poke fun at them, "Why did girls always have to be so giggly and weird? Why couldn't they just act normal?" [location 269]. The author writes this book from the boy's perspective and she also describes Eunice as a tomboy of sorts. However, she does choose to describe the norm for girls' interests in a rather clichéd manner. Eunice has 49 sisters and she claims that they are all boring and interested only in materialistic things. Female readers can take offence from this or rather understand that they can celebrate their uniqueness and be interested in whatever they like.

A comical reference to myth appears when Demon is invited to Amphitrite's palace. She wants to hear the latest gossip, yet the "news" she refers to are, in fact, myths: "is it true about Eos's poor husband being turned into a grasshopper? Did Apollo really give that stupid Midas asses' ears?'" [location 383].

Poor Demon is dumbfounded, but repeats things he learned from his nymph friends, who told him about Io being turned into a cow. This is an entertaining way to present the ancient myths as gossip for a mythological queen and their mentioning might make the readers more interested in learning about these myths as well. Furthermore, any adults reading this story would be amused by these comments.

The author also hints at Phaeton's myth, yet without narrating it completely. Helios tells Demon, "I must go and see what my son Phaeton's been up to.' He chuckled, smiling his scary smile again. 'Naughty little scamp’s always in trouble – why, he even tried to drive my chariot the other day before I caught him.'" [locations 481–482]. If the readers are familiar with the ancient myth they might be amused by its happy ending here and if not they may wish to read more about it. The author deliberately chooses to end the myth happily, with no loss of life for Phaethon. She wants to keep the light tone of the book without telling how a young boy lost his life. (The only fatal myth that is mentioned is Heracles' murder of  his family (told in the first book), retold in order to portray Heracles as the story’s main villain).

The review refers to the Kindle edition (9781848125490).

The illustrator of this Kindle edition is David Roberts and the publisher is Piccadilly Press, London.

See "Addenda" under Beasts of Olympus (Series, Book 1): Beasts Keeper.