On the crystalline planet of Yewa, the Gardens of Kubuntu are a true Eden, said to be the most peaceful destination in the universe. At least, until the Doctor and Ruby arrive. Ancient rivalries between Yewa and its more prosperous sister world of Bia are being stirred by forces unknown, threatening to plunge its people into anarchy. With Ruby swept up in the fire of the Yewan rebellion, the Doctor finds dark secrets buried deep in the planet’s ancient history – and his hopes for a lasting peace hanging by a thread. For sinister guardians stalk the Gardens of Kubuntu, while an implacable enemy plots in the shadows – and in plain sight...