Dark River (originally published under the title The River) will keep you on the edge of your seat until the very last page.
A Warning from the Publisher:
If you have come this far, it is likely too late. Readers who have experienced the first nine volumes in A Series of Unfortunate Events by Lemony Snicket are usually so weakened by their dreadful knowledge of the Baudelaire orphans' story that they spend most of their time moaning and weeping, and have no strength to read The Slippery Slope, The Grim Grotto, The Penultimate Peril, or The End.
If, by chance, your moaning and weeping is more or less under control, there is no need to further risk your physical, emotional, and literary health by reading the four remaining volumes in the series. It would be better to regain your strength by spending your time indulging in less alarming activities, such as whistling or making cupcakes for the elderly. After all, this collection contains all of the calamities in the last four volumes of A Series of Unfortunate Events, including abandoned condiments, cigarette smoking, a shocking revelation, a ridiculous laugh, a fearsome storm, a herd of wild sheep, a truly haunting secret about the Baudelaire parents, another shocking revelation, and Phil. There is no need to exposure yourself to such atrocities, not after all you've been through already.