Thesis has been struggling as a professor for years. There is an island in Luna Bay that holds her spellbound, because nopony has explored it in recent years. It's right nearby, but there seems to be a lack of interest in the place.
That may have to do with the poisonous plants dominating the flora on the island. It's a choked mess of poison and vines, and inhospitable to all but a single tribe of ponies. How do they survive? Why do they live there and not leave?
After a convincing speech, she gets the funding to manage the trip, but despite the hardships in getting volunteers and supplies, she's on her way soon enough. What she and the others find, isn't at all as great as she thought it would be.