When a girl called Ali pockets a silver orb that falls from the sky, little does she realise it's her ticket to seeing the universe! Desperate to retrieve the mysterious object, the Ninth Doctor agrees to let her join him on a dangerous trip to ancient Babylon. Together they must join forces to stop a giant Starman from destroying Earth before it's too late!
to be added
- Ninth Doctor
- Ali's dad
- Ali's mum
- Rose Tyler
- Mickey Smith
- The Doctor describes humans and meerkats as the only two "halfway sentient" creatures on Earth circa 2005.
- The Doctor mentions some of his previous companions; Susan, Barbara, Ian, Prince Egon, Jamie, Polly, Ella McBrien, Sarah Jane Smith and Leela. Egon and Ella are new companions referenced for the first time in this story; it is not known which Doctor they travelled with.
- The Doctor talked to the Exalted Holgoroth of All Tagkhanastria, pretending to be an emissary from the Crab Nebula.
- Karkinians come from Karkinos.
- Ali learnt about TARDISes and the Time Lords at college. She was taught they were extinct.
- The Doctor compares Ali's good observation skills to Sherlock Holmes. She does not know who he is.
- Gurgurum mentions the conquests of Eshunna, Elam, Larsa, and Mari as examples of Babylon's might.
- The Tigris and Euphrates rivers make up the borders of Babylon.
- The soil of Babylon is fertile, allowing lots of fruit trees, date palms, and fields of wheat to grow there.
- This is the second of the eShorts in which the Doctor is not depicted as travelling with one of his TV companions, the first being Spore. It is also one of the earliest depictions of the Ninth Doctor in an adventure with a non-TV companion, second only to What I Did on My Christmas Holidays by Sally Sparrow in publication.
- The final chapter retells the final scene from Rose, but from the Doctor's perspective.
- An audiobook of the story was read by its author, Charlie Higson.
- The Doctor mentions that he once had a hand similar to that of a crab, in a body "far far away". (PROSE: A Big Hand for the Doctor)
- The Doctor has just left Earth after defeating the Nestene Consciousness with Rose Tyler. He is convinced to return to Rose and ask her to be his companion by Ali. (TV: Rose)
- The Doctor says he is only a warrior if he has to be. (TV: The Night of the Doctor)