Viewers won't miss much of the 'Summer City' ('Reign of Fear' for us Yanks) plot if they fastforward to the last forty minutes of this movie, as much of the movie is just filled with scenes that look like minute preparation for a string of Mentos commercials. The ample cheery scenery and happy 70s romp music seem very contradictory to the thriller mood. Add to the mix a indiscernable audio (not that the dialogue matters much, anyways) and slurred slang, it is a pretty boring movie.
Four friends--I'm not sure if they're supposed to be teenagers (none of them look younger than 25, but there's some scenes where they look like they're at a school dance)-- take a road trip to kick back, hit the pubs, and go surfing. Tension builds among the group between Sandy, a quiet young man who is angered by the obnoxious, womanizing Boo who seduces a teenaged girl while on their trip in one of his usual one night stands. Meanwhile, the girl's psychotic dad is also looking for Boo out of revenge for what he did to his daughter. Boo is in for a major wake up call. This is essentially the only substance of the film, a very simple story with no major drama or action, and even a let down ending.
Despite Mel Gibson being heralded as the star of the movie, his named marqueed in large letters, he is pretty inconsequential to the movie, and has a very minor role.
What could've been more like a version of "Deliverance," turned out to be a very boring movie that suffers from many faults as far as story and production values.