Mia wakes up one morning and can't get out of bed. The doctors are baffled as she becomes paralyzed, but an unexpected discovery solves the mystery. Then meet Mike, a diver who was unknowingly stung by an Irukandji jellyfish and only sought medical help hours after the venom had taken orce in his body. Was it too late? Meanwhile, as Carol is alone in the ocean, she as a sea lion attacked her, leaving a gaping hole in her leg. Carol fights for her life as she tries to get to shore.