The Rig

It was the wrong day for a picnic!  Mitch and Ryan head for the   oil rig abandoned after a strange accident and spot a drifting   yacht.  Searching it they find a terrified young woman who says   her host was pulled off the yacht by a weird sea monster.  They   have to abandon the yacht and use a rubber life raft to reach   the oil rig where the gelatinous green stuff catches them.