One night Nancy Lyon awakes in pain and dies shortly after - poisoned with arsenic. Her family immediately suspects her husband Richard, who left her temporarily the year before because of an affair. Especially Nancy's brother is keen on getting the children away from the suspected murderer. All evidence points against Richard, but in court Richard surprisingly presents proof that his wife had depressions and maybe killed herself - or are these proofs just fake? -- Depicts an authentic case.

"A", a member of a student protest organization, becomes disenchanted by his group's inability to effect real change. Emboldened to pursue more radical methods by the older, experienced leftist organizer Despard, "A" unwittingly becomes party to a labor strike that turns violent. Ultimately held responsible by the authorities for the fracas, "A" allies himself with terrorist Leonard, who intends to avenge those jailed in the protest.

Two teenagers who have been engaged in pre-marital sex become the prime suspects when the girl's disapproving father is mysteriously murdered.

Police chief Brody must protect the citizens of Amity after a second monstrous shark begins terrorizing the waters.