Epic Pictures is responsible for V/H/S so at least there's a chance for this movie with a preposterous title and even crazier plot. It's got Franco Nero, so it's clearly worth the watch. Just check out his rad hat. Also the title was formally Nymph which was changed for the US release though I'm not sure if it's been changed worldwide at this point.
Available on XBOX digital (exclusive August 26th) and DVD
Synopsis from Epic:
Two beautiful young women go on an exotic Mediterranean vacation and uncover the water lair of a killer mermaid hidden beneath an abandoned military fortress. What was once a carefree adventure becomes a deadly fight for survival. Starring Franco as Niko (Django), Kristina Klebe as Kelly (Rob Zombie's Halloween), Natalie Burn as Lucy (Expendables 3), and Drago Micanovic as Boban (Rocknrolla).