Agatha Christie is an author you can rarely go wrong with, and Hallowe'en Party is no exception. The book is another Hercule Poirot mystery. In this one, his friend Ariadne Oliver attends a Halloween party where a girl named Joyce claims that she once saw a murder. Later in the night the girl is found drowned in the barrel of apples.
The characters are fairly standard, though they're fairly entertaining. The dynamic between Mrs. Oliver and Poirot is particularly charming. The dead characters and the eventual murderer are also given some degree of depth. Other than that, the characters are serviceable but shallow.
The plot mostly consists of Poirot speaking to the various suspects and witnesses. It drags a bit at points, but quickly picks up. The twists are all well built up, and nothing feels like it comes out of nowhere. All the pieces fall together in a satisfying way.
This book is also sold as "A Haunting in Venice". This is because the new Hercule Poirot movie is loosely based on this story. However, the key word is loosely. So, if you watched the movie first, be aware that these two stories have almost nothing in common (aside from the main character).
I would recommend this book to fans of Agatha Christie and mystery fans in general.