Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Gotta rate it as a horror film.

1st off I loved it. It was hysterical. One of my favorite black comedy's ever! It's not scary at all. This was another entry in the early 1980s slasher cycle of films that began with Halloween (1978) and Friday the 13th (1980), and like many of the copycat slasher films features a holiday date-themed titles. Happy Birthday holds some promise over the others in that it had a quite respectable director at the helm - none other than J. Lee Thompson, who had made films such as Cape Fear (1962), McKenna?s Gold (1968), Conquest of the Planet of the Apes (1972) and Battle for the Planet of the Apes (1973). Cape Fear, in particular, is a masterful film noir psychological thriller. The prowess that Thompson displayed there is something that should set any slasher film light-years ahead of the competition. But fails miserably and finishes with one of the funniest horror films ever. Not scary at all. 5 stars as a comedy.