Host Planet Earth was a BBC

BBC

The British Broadcasting Corporation is a British public service broadcaster. Its headquarters is at Broadcasting House in the City of Westminster, London. It is the largest broadcaster in the world, with about 23,000 staff...

radio serial consisting of six half-hour episodes which were originally broadcast in 1965. It details the course of a strange disease which first affects scientists working on a British rocketry programme. When British astronauts fall prey to the sickness in space, can they be allowed to return?

Episodes

1. "The Beginning"
2. "The Empty Minds"
3. "The Pattern Emerges"
4. "The Gemini Factor"
5. "The Arrival"
6. "The Price of Freedom"