@ Chris:
The game was developed (like the TV programme) with the assistance of Hallie Rubenhold, an author and historical consultant who had published books on life in Covent Garden in Georgian London:

http://www.hallierubenhold.com/

She reviewed all the game scripts for historical accuracy during the game's production, and many changes were made to make sure that the content and situations were historically accurate and consistent with records of London in this period. Obviously some of the actual narrative is invented for the game, but all the period details and references are accurate.

Disclaimer - I'm the commissioning editor for education at C4 who worked with Alice on the project. We're taking extreme care with our gaming projects this year to make sure that when we refer to history/science or other educational material that we work with qualified experts in these fields. For example - we're developing an ARG at the moment that inlcudes references to genomics, so we're in discussion with the Wellcome Trust to work with the scientists at the Human Genome Project at the Sanger Institute. We believe that you can make an entertaining, exciting game without compromising on the accuracy of the educational content.