This book explains the time before, in-between, and ending of Darth Maul from Star Wars: Episode I: The Phantom Menace. Even if you didn't like the movie, the Expanded Universe material on him is very interesting, since he died at the end of the movie... supposedly.
It explains his training, his relationship with his master, his plans to end the Jedi, his birth planet and how Lord Sidious snatched him (but not the complete picture... see the novel called Darth Plagueis,) how he got his double-bladed lightsaber, his dealings with the Neimoidians, their resourcefulness in tracking down the Queen and her Jedi, h the brawls involved in getting close enough to attempt to assassinate the Jedi and the Queen, how he didn't defeat Qui Gonn Jinn from the first encounter on Tatooine,the explanation of the final battle between the two Jedi and himself told through his Master's vision, and his Master's plot to ascend to the Chancellorship of the Galactic Republic.
Lord Sidious ends the journal entry by finding the journal, reading it, and completing it with a summary of the basic plots of the movie, what he wrote in his journal, and his untimely death.