Kagewani revolves around a video blogger who stages cryptid sightings for views, but his crew is brutally killed by a real monster, forcing him to confront the reality of these creatures' existence. On a separate front, students on school grounds are hunted by a massive, sandworm-like beast, prompting a desperate fight for survival. Researcher Sousuke Banba, driven by the mysterious keyword "Kagewani," investigates the attacks, but his inquiry is complicated when a pharmaceutical company, Sarugaku, starts to interfere with his work.