The Last Oasis
Planet Earth has been plundered for resources to the point on instability. Many upper class members have abandoned and fled the planet before it gives out while leaving the rest of the world to die.
Wildlife started evolving from toxic residue as well as the remnants of experimentation for the better or worse. Animals became more monstrous with some becoming humanoid, dangerous, or holding mysterious powers. Plantlife while being scarce, started to grow hardier and more efficient as if it were an attempt to save what's left.
Upper class society (often called the "escaped") sometimes comes back to reanalyze and study the crumbling planet in areas nowhere near the leftover civilizations and forests and often assume earth is just a dead wasteland.
They are so unaware.