Doctor Quist and Doomwatch become embroiled in an inquiry into the heart-transplanting practices of Doctor Patrick. Several uncomfortable questions are raised: what has he been doing to a newborn baby that has been placed in his care, and should genetic engineering be permitted in society?

When a lifeboat crew discovers a luxury cruiser adrift in the English Channel, they find on board are a group of wealthy pop stars and their girlfriends, one of whom is dead. Doomwatch investigate, and discover that the death was not from drug abuse as was previously suspected; instead they begin to uncover the facts behind the dumping of a deadly chemical warfare compound in a deep sea trench, which seems to be far from dormant.

In order to decide on new proposals for dealing with the dangers of pollution on the environment, Doctor Quist assembles a conference amongst the world's top scientists. But soon several of the delegates become ill, apparently from food-poisoning. However, Quist becomes suspicious, and suspects that the sickness may have been caused deliberately.

In an effort to prevent unofficial strikes by its workforce, a company in the North of England decides to use the latest scientific discovery, and attempts to manipulate both the working and the private lives of its employees by bugging them with listening devices. However, when Quist hears of this underhanded practice he is furious and decides that the only way to stop the unethical management is to turn their own method against them.

A military plane ditches into the sea whilst carrying three nuclear weapons on board. While the RAF mounts a search mission, an unidentified object is washed up on the shore near Byfield pier on the south coast of England. It is found by two men, Geoff Harker and Sam Billings, who decide that it must be a weather detecting device, and so begin to strip it down for parts. Toby is sent to investigate the device, but he soon finds himself faced with the terrifying prospect of disarming a very live bomb.

John Ridge apparently suffers a breakdown from the pressure, and decides that, due to the excessive threat of pollution on the environment, drastic steps should be taken. He steals some phials of the deadly virus anthrax and holds the government to ransom: unless his anti-pollution terms are met, he will destroy humanity by releasing the virus in a number of major cities. A race against time begins. Can Ridge be tracked down before it is too late?

An inquiry into Doomwatch is begun following the events surrounding Ridge's breakdown. Meanwhile, Quist is summoned to a large country estate in Scotland, where he finds himself offered a new position with both power and wealth in the private sector, but only if he will curtail his investigations into a new drug called disocyanate. Back in London, the Minister decides that it is time to place his own man within Doomwatch, and so despatches Commander Neil Stafford to join the team.

Many years ago, Quist worked on the infamous Manhattan Project, which was instrumental in the designing of the atomic bomb codenamed Fat Man, used to obliterate the seaside port of Nagasaki in World War II. This involvement has continued to weigh heavily on Quist's conscience ever since. Hearing the phrase "Say knife," he recognises a potential threat - one that is tied into a break in at a plutonium base. A group of young student activists has stolen several radioactive fuel rods, and are planning to construct their very own atomic device.

A revolutionary new lipstick goes on sale, containing pheromones designed to act as an aphrodisiac in order to make the wearer more attractive and desirable to men. This prompts Quist and Bradley to begin an investigation into the effects that pheromones have on people, and how they can alter the illusion of free will.

Ridge continues his ecological crusade by warning against the dangerous side effects of the chemical insecticide known as D.D.T. upon the world's developing countries. He stages a publicity stunt by flying in an Indian family and setting them up in a tent in the middle of London's St. James Park. But the prank backfires when it is discovered that one of them is suffering from malaria.

Doomwatch is alerted to a laboratory where a new toxic gas is being developed for military use, available in a 'handy' aerosol can for easy application during conflict. But Quist and Anne's enquiry soon leads them to doubt that the scientists' safety measures concerning the storage of the gas may not be as secure as they think.

Quist is concerned by the fact that, approximately every one hundred years, certain extreme weather conditions arise which lead to an increase in the water level of the Thames - and just one inch higher would result in the whole of London flooding. Even more disturbing is the fact that this increase is imminent.

When John Ridge's father, Wilfred, becomes seriously ill, he decides to devote all his time to looking after him. Wilfred is then taken to hospital and put into the care of Doctor Cordell, but shortly afterwards he dies. Ridge is suspicious, and his investigations uncover a disturbing fact: Doctor Cordell is an advocate of euthanasia.

Dolphins have long been established as highly-intelligent creatures, and the United States Navy has now begun using them in their new program. They are training the dolphins to act as underwater saboteurs, able to attach magnetic explosive devices to the undersides of enemy ships. Quist investigates the matter, and discovers that these apparently docile creatures are capable of becoming deadly killers - something that he experiences firsthand.

Astrophysics lecturer Neil Tannahill receives an enigmatic note from Dr. Spencer Quist, former head of Doomwatch, and finds himself drawn into a sinister conspiracy involving Soviet nuclear waste secretly stored at a British nuclear facility.

Astrophysics lecturer Neil Tannahill receives an enigmatic note from Dr. Spencer Quist, former head of Doomwatch, and finds himself drawn into a sinister conspiracy involving Soviet nuclear waste secretly stored at a British nuclear facility.

The first nuclear-powered rocket, Sunfire One, is sent into space with the first British astronaut, Dick Larch, on board. After the rocket enters Earth orbit, Larch enters an incorrect course alteration, and fails to see the error indicator, which results in Sunfire One splashing down in the sea. Quist is asked by Doctor Goldsworthy to determine whether Larch is suitable for any further missions, as another such mistake could result in the spacecraft becoming a nuclear bomb.

A vicar collapses during a sermon, and there are seemingly unrelated events, one involving John Ridge. The answers are out there, but are obscured by big business and profit margins.

A deadly new strain of typhoid is sweeping through local schools. There is a treatment, though, and the team at Doomwatch endorse this in spite of its side effects.

After a long-haul flight Dr Quist's reputation is put seriously in doubt when he arrives drunk to a meeting with the Prime Minister. Is it a simple case of jet-lag, or sabotage?

Two thousand animals are found dead in the Somerset countryside. Doomwatch investigate whether or not a new pesticide is to blame.

The Doomwatch team investigate the mysterious outbreak of a deadly subtropical disease which somehow has cropped up on an isolated island off the coast of the UK.

The death of a young man off the Scottish coast leads to the Doomwatch team investigating a cover up in the case of a sunken ship, and the discovery of a revolutionary life-changing science.

The government wants direction for the possible construction of more high-rise apartment buildings. Fay Chantry is asked to live in one and supply a report based on her experiences.

The Doomwatch team look into serious health issues experienced by male workers at a Welsh battery farm.