Instruct: Classify the given review into positive or negative sentiment.
Query: One of the most well-written mysteries I've read

Excellent. The only reason this book receives four stars as opposed to five is the sadness of the story. The prose is very fine. Although intellectually one can realize a few flaws (a few very convenient plot points and cliches), they do not take away in the least from the intuitional impact. The descriptions of Venice are also great, and accurate, if overly melancholy, according to my father, a former resident. Read it, but not on a gloomy day.