Episode list

Gerrard, Boult and Franklin are all behind the effort to get a big balloon launched on a journey to the edge of space, Balloon veteran Cmdr Murray has called off the launch six times on the grounds of danger. His true motives can only be revealed by a seventh attempt.

A rare radioactive isotope goes missing and may be in the hands of a child unaware of the danger it poses.

Space research and freedom makes uneasy bedfellows.

Undersea exploration becomes an experiment in survival.

R3 is involved in an experiment in survival after a nuclear attack.

A local shopkeeper decides to take action against R3.

R3's faith in itself is put to the test.

A virulent new pesticide has an immediate and dramatic effect - the mass extermination of wildlife.

Can industrial man even be satisfactorily replaced by machinery?

Boult, a man used to dealing with things and ideas, not with people, finds himself facing a military interrogator.

After a lifetime of fruitless research, Andrew Furness is facing tragedy.

When Richard Franklin gets mixed up with TV, it exposes an unexpected side of his personality.