Blending elements of horror with a medical mystery narrative, this film explores the consequences when individuals become infected by parasites—tiny organisms lurking in water, soil, and even the air. The film recounts the experiences of those affected, highlighting the efforts of doctors and scientists as they race against time to solve each case. Biologist Dan Riskin, along with medical professionals and experts who have firsthand knowledge of these incidents, spearheads the scientific analysis of each parasitic threat.