After her parents died in a fire and her grandfather disappeared, Meg Whitlock thought life was at an impasse. But upon learning that the pocket watch that her grandfather left her is actually an intricate key, Meg, with the help of a groom named Will, learns about the existence of the Entertainers: members of an elite secret society dedicated to discoveries and shrouded in mystery. Now the Entertainers have gathered in London, and Meg has decided to join their ranks. But being the first girl in the Order is very difficult, and now that Will is far away in Scotland, Meg is afraid that she has no one to trust but herself. Her fears are only confirmed by the sabotage that happened at the academy - and each modified invention does more harm than the previous one.