How Many 'Series Of Unfortunate Events' Books Are There And What Are They About?

In total, there are 13 books in the series. The 13th book, 'The End', was released on October 13th 2006.

The books are as follows (in order):

The Bad Beginning
The Reptile Room
The Wide Window
The Miserable Mill
The Austere Academy
The Ersatz Elevator
The Vile Village
The Hostile Hospital
The Carnivorous Carnival
The Slippery Slope
The Grim Grotto
The Penultimate Peril
The End

The books are written by Daniel Handler, under the pseudonym of Lemony Snicket. The books tell the stories of the Baudelaire orphans, who are left under the care of Count Olaf after their parents perish in a mysterious fire. Olaf is an unpleasant man, and tries to steal the orphans' fortune, which their parents left them.

Mr. Poe, a friend of the orphans' parents, is oblivious to Count Olaf's unpleasantness up until the end of the first book, when he realises that Olaf is actually a villain. Some of the other stories have Count Olaf attempting to steal the orphans' fortunes by using various disguises to get near them. The children are taken care of by a host of guardians, most of whom Count Olaf murders. In later books, the children discover a secret organisation, V.F.D., which they discover that Count Olaf was part of. They uncover more about this mysterious organisation as the books go along. After the seventh book, The Vile Village, things take a drastic turn, with the children on the run from the law and Olaf no longer needing disguises.

The books have the theme of unhappiness and bad luck, hence the final book, The End, being released on Friday 13th in October 2006.