Following the death of their daughter Bella in a freak accident, Adam and Eve Smith are given the opportunity by the Storyteller to seek answers to some fundamental existential questions. Despite the risks and dangers, Adam and Eve, together with their unbelievably intelligent dog, Luke, decide to set out on a journey with the Storyteller in the Storyteller's yellow camper van.

Adam and Eve, joined, after a chance meeting at Fleet services on the M3, by the insatiably curious Rambler and his mentally challenged nephew Numpty, soon find their search is to be impeded by Grimrose, a shapeshifter, and his master, the Breaker, Nick Peters, who tells the questors they are wasting their time.

The questors first excursion is to the Garden of Eden, near Hook off the A31, where they are granted an audience with God. Things do not go well. Eve alienates God who decides to impose a terrible punishment on the questors, a punishment from which they are saved only by the intervention of a blind traveller, Kit, whom God wrongly believes is his long lost son. While in Eden, the questors visit one of Eden's industrial estates where they meet Rodney and Derek, two angels who constitute God's R and D department. Rodney and Derek fill the questors in on how the universe and humanity was created.

On leaving Eden, the questors travel in the camper van, equipped with a paradox device and an exponential drive, to Mount Strobilos in the Caucasus of some thousands of years ago, where they are hospitably entertained by the titan Prometheus who gives them his version of the birth and destiny of man. While there, Nick Peters makes a determined effort to persuade the questors to abandon their quest. When Adam and Eve reject his advice, he warns them he will destroy them.

The Storyteller now conducts the questors on three excursions to witness three great beginnings: the creation of the universe; the birth of life; and the emergence of human consciousness. These extraordinary experiences challenge Adam and Eve to reframe their questions and re-evaluate their quest. Throughout these excursions, uncle Rambler displays his not always relevant erudition and nephew Numpty pursues his almost always irrelevant enquiries.

When the questors return from their excursions, they are seized by the Breakers. Eve is put under house arrest at Poulner Hill where the master Dawk, Despiro Nihilopificus, attempts to deconstruct her mind; Adam is incarcerated at Breaker head office where he is put through an ordeal in hell, a great underground construct beneath the Breaker offices.

The Breakers are fearful Adam and Eve could trigger the Fourth Beginning and they, with the help of their Dawks (deconstruction applied with kindness), will do anything to prevent it. But they reckon without Adam and Eve's qualities and strength of character - and the powers of the enigmatic blind man, Kit.