So you’ve decided to jump into a black hole. Good news: as long as the black hole is big enough you can sail through the event horizon without harm and get to experience the interior of the black hole before you’re annihilated by the central singularity. Or so we once thought. These days, quite a few physicists believe that the only way to avoid horrible contradictions in fundamental physics generated by black holes is for all them to be surrounded by screens of extreme energy that prevent anything from ever entering the event horizon. Sounds outlandish? Welcome to black holes. So let’s find out why many of our most brilliant physicists take these black hole firewalls deadly seriously.