The result is a fairly taut 80 minutes with so much female nudity I started wondering halfway through if this movie had been made in the Go-Go 70's. Nope. The film-makers handle the scares and the grotesque with a grungy, occasionally startling style -- the 'true' appearance of the Siren comes as a nice reveal. The bachelor party members are not impressively delineated as individuals, but the characterization is passable and the performances fairly naturalistic.
The Siren's club is a nicely handled conceit -- the supernatural bar that you should never have entered. Its owner, occultist Nyx, bears a weird resemblance to Paul Williams. There are some solid, fantastic bits involving memories, magic, and Medusa. The film also shows us brief glimpses of all the supernatural events going on at the club without going into them, making the glimpses that much more effective at inspiring unease. Overall, an enjoyable horror movie on a limited budget from Universal's Chiller Films brand. Recommended.