In the autumn of 1879, an intelligent, artificially-created being - outwardly a young woman called Maria - arrives in London under the protection of biologist Professor George Hobson. Hobson gathers a few close friends and reveals her existence, explaining that she is the result of a research programme undertaken by a dynasty of unethical scientists, the von Frakkens - all now dead. Unknown to Hobson, one of his friends, Jabez Pell, is linked to an underground scientific organisation, the Promethean Society. Set up in the early 1800s, its aim is to conquer death by whatever means possible. Pell immediately recognises the potential that Marias regenerative abilities can offer to the Prometheans - but after his attempt to kidnap her turns deadly, Maria goes on the run.