The Lake of Souls is the 10th book in The Saga of Darren Shan and is also the first in the 4th and final trilogy in 'The Saga' called The Vampire Destiny Trilogy. It reveals a lot about the character of Harkat Mulds mainly and introduces a new character called Spits Abrams. This book also adds many more questions that will be answered in the next two books. Also, this book is the longest in the series.