The Poison Waves (Secrets of the Sky, Book Two)

Kiya and Kinjal return to the enchanting Kingdom Beyond, where they learn of a dire threat: the water pari, winged merpeople, are being poisoned. Summoned by Princess Pakkhiraj, the twins must use their wits to uncover the source of the danger before the malevolent serpent king Sesha catches wind of their mission. With the help of their flying horses, Snowy and Raat, they embark on a new adventure to save the magical realm.