Carbon dioxide levels were at critical levels in the Earth’s atmosphere. Even the US President agreed the problem was real. Deforestation was a major contributing factor.
Genetic engineers had developed a transposon that when introduced into trees markedly reduced the amount of carbon that a dead tree released into the atmosphere.
Application of the gene technology to mature trees meant that deforestation could continue even faster.
But the trees were smarter than we realised. They had their own underground genetic engineers. Pretty soon an unsuspecting human race was being affected by a range of deadly airborne viruses that the trees had generated. Whole cities became de-populated of humans one after the other. The ultimate solution to reducing carbon dioxide generating practices had arrived.
The Inspector and Cat 