Something strange is happening in the Sea of Cortez. Whales are beaching for no apparent reason and the local hammerhead shark population, previously believed to be fished to extinction, has suddenly reappeared. Marine biologists Maria Quintero and Kevin Hoyt have come to investigate with a television producer in tow, hoping to get footage that will land them a reality TV show. The plan is to have a stand-off against a notorious illegal shark-fishing captain and then go home. Things are not going according to plan. There is something new in the waters of the Sea of Cortez. Something smart. Something huge. Something that has its own plans for Quintero and Hoyt.