This four-episode documentary tells in depth the story of Amherst, Massachusetts, a chemical analyst at the drug lab, Sonja Farak, who gradually became addicted to drugs during his long-term exposure to drugs and could not extricate himself.To cover up her crimes, she tampers with thousands of test results, which eventually triggered a judicial storm.However, it was her betrayal that unexpectedly uncovered the truth of hundreds of unjust cases, prompting people to reflect deeply on the judicial system.