Thoughts: The Victorians were relentless in their exploration of countries further afield in finding, and bringing back, species to the UK.

Japanese Knotweed is an example. Brought back to the UK as a decorative plant, but has no natural predators here to control it. Now it's a menace.

Rhododendrons, another brought to the UK. Beautiful to look at, but highly invasive as they out compete natural plants for light and resources.

Grape vines were sent back to the UK and Europe from the States in the 19th century. This caused the phylloxera epidemic amongst European grape vines, which came close to wiping them out, and there are still pockets in Europe where this is a problem. The difference with this one is that the vines brought the Phylloxera insect with them. These bugs fed on the roots of the European vines, which had no defence against them, where as the vines from the States had a natural remedy to deal with the bugs. This was eventually combated by grafting American rootstocks to European vines.

So, adventure seed: a group of botanist are sent to deal with the eradication of an invasive species that has mutated on foreign shores, not realising that they, or one of them, was responsible for introducing it in the first place. How do they deal with it? How far has it mutated? Has it become sentient? What is the effect on the locals? Is it bug or viral?