When Grubb, an orphan and runaway chimney sweep, entered the wondrous world of the Odditorium, his life changed forever. Apprenticed to the mechanical marvel's strange proprietor, Alistair Grim, Grubb unfortunately must settle into his new position on the lam, as the whole of London is convinced that Alistair Grim is a villain bent on mass destruction. Grim, however, has come up with a plan to expose the real villain: Prince Nightshade, a wicked necromancer who wants the Odditorium's power source for himself.