A blue whale has mysteriously beached herself in Marin County, CA. Nearby, a teenage girl, Sydney, receives a DM from a man inviting her to play an online game. Her sister, Emily, joins in and the two are taken on an ominous journey from which they can’t escape. Their high school mirrors an aquatic ecosystem where the cheerleaders are the sharks, the chess club is the phytoplankton, and the older sister Sydney and her friends are herring. Emily’s only refuge is underwater, where she competes as part of the school’s swim team. As each day passes, the sisters complete another task in the deadly game while their marine biologist parents struggle to rescue a series of stranded whales. Inspired by real events, The Blue Whale examines the relationship between violence and social media while illuminating the climate crisis and its effects on marine life.