Self-defense tear gas cannisters are becoming popular as a way to protect oneself from criminal attack. But tear gas requires intelligent and informed use. The film teaches the distinction between crimes against a person and crimes against property, thereby demonstrating legal and illegal uses of this weapon. It shows why, to be effective, tear gas must be sprayed liberally in the face at close range. It shows how to use the chemical agent tactically, to allow its user time to escape. The film shows the actual effects of tear gas on two volunteer subjects, demonstrating that while tear gas is generally effective, it can affect some people only minimally. (Author abstract modified)