
She and Francis separately manage to extract from the lichen a new drug, dubbed Antigerone, which slows down the body's ageing process. The two central characters are Diana Brackley and Francis Saxover, two biochemists who run parallel investigations into the properties of a specific species of lichen after Diana notices that a trace of the specimen prevents some milk turning sour.
Wyndham speculates how society would deal with this prospect. The plot concerns a young female biochemist who discovers that a chemical extracted from an unusual strain of lichen can be used to slow down the ageing process, enabling people to live to around 200–300 years.

Trouble with Lichen (published 1960) is a science fiction novel by British writer John Wyndham.
