The Shadow Constant

Someone is keeping watch over the machine. Should it ever have been built?
Suspense and Sci-fi readers will love this page turner from a USA Today bestselling author.
The lure of the find behind the loose hearthstone at Hazleton House was too great. The schematic excited Evan, Reenie and Ivy for different reasons but it is Kayla who actually begins building it. Her ability to focus to the exclusion of all else is just one of the effects of her Asperger's.
The scribbled initials E.W. were merely a curiosity until it's discovered they belong to Eli Whitney. But strange footprints and disturbing visitors let Evan know that the theft of his sister's prize schematic isn't just a coincidence.It becomes obvious that the generator has no apparent power source. And Eli Whitney was only the first to die because of the machine.
Soon they realize their enemies are much bigger than they had imagined and the threat the device poses could topple an empire. The secret now threatens those at Hazleton House.
Who is trying to stop them?
Winner: Booky Award for BEST Thriller & Suspense Book 2013Winner: Booky Award for top 12 books of 2013Finalist: Beverly Hills Book Awards for New Fiction and Suspense 2014Finalist: Eric Hoffer Best Book Award 2014Silver Medal: Indie Excellence Award for Mystery/Suspense 2014