The story has a clever premise --Ben Franklin, while in London in the 1750s to negotiate with the Penn family as agent of the colony of Pennsylvania, investigates the apparent murder by electrocution of the porter at the Vulture Tavern, which leads him to the Hellfire Club. Despite the clever concept, I did not enjoy this book as much as I expected I would. It seems to emphasize the more sordid and grim aspects of London life at the time. ( )