Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Must have movie if you liked Firefly

Serenity was what season 2 of Firefly would've been had it been made. If you own the Firefly DVD series then do yourself a favor and buy Serenity as well. It's a fast moving movie and ties together a lot of loose ends from the Firefly TV series, which is also a must have DVD set. It's simply one of the best written TV shows in the last 10 years. There are also soundtracks for both Firefly and Serenity that are thoroughly enjoyable to listen to.