The more fun version would be where black holes do not evaporate, at which point it will still be a very long time before it's a problem, we need to worry about Andromeda crashing into our galaxy and the sun becoming a red giant first.
Or maybe they are the dark.
The Sun's dying and will become a red giant (about 5 billion years to go), but it's luminosity is currently increasing, so our rock will become a scorched Earth in around a billion years. Then there's the potential for meteors, climate-change, antibiotic resistance, or millions of tiny black holes to do us off first (how quickly do black holes grow, anyway?)
Colonising other planets and other solar systems seems the only viable solution to the long-term survival of the human race.