The Web of Time is stretched to breaking. History is leaking like a sieve. In the Citadel of Gallifrey, the Time Lords fear the end of everything that is, everything that was... everything that will be. The Doctor holds the Time Lords’ only hope — but exactly what lengths will the Celestial Intervention Agency go to in their efforts to retrieve something important from within his TARDIS? What has caused the Imperiatrix Romanadvoratrelundar to declare war on the rest of creation? And can an old nursery rhyme about a monster called Zagreus really be coming true?