The Lake plot
"A nurse returns to her home town to care for her dying father, and finds everyone she knows there has undergone a bizarre personality change."
Nurse Jackie returns to her hometown to care for her critically ill and alcohol-addicted father Steve. Despite having only a short time to live, he is improving rapidly. Jackie is relieved but notices that her father has also more or less changed his character. She notices that more people are starting to behave strangely and discovers that it has something to do with the water of the nearby lake.