The setting is earth some year wayyyy in the future.
Because of runaway global warming caused by green house gas emissions planet earth became essentially uninhabitable; a giant ball of hot gas clouds. Everybody died.
Some alien race comes exploring for resources or whatever, but when they get here they find the planet is actually inhabited by the ghosts of all the angry souls that tried to warn people about our impending doom, along with some weirdly evolved flora and fauna maybe idk.
Obviously I haven’t fleshed out all the details, but it sounded like the seed of a cool idea so I wanted to share it and see what people thought before I forget I ever had it.
It’s not perfect 1:1 but you might find inspiration in some of the environmental storytelling of the game Sable.
Maybe a tiny subset of the human population survived and evolved too? I could see a combination of that going somewhere.