Doctor Who: The Masque of Mandragora

An encounter with the living energy structure known as the Mandragora Helix leads the TARDIS to 15th century Italy. Between palace intrigue, the machinations of a sinister cult and a rogue fragment of Helix energy, the Fourth Doctor and Sarah have their hands full. There is not much time, for when Mandragora swallows The Moon, it will be time to strike.