After a scene in the first level, a door appears behind the main character, which can take her back to the island where the game starts.
When I first went through that door, I got a black screen when I got to the island, but the controls were still responsive (I could enter the pause menu and I could feel the controller vibration and hear the sounds from jumping).
After reloading the save, I didn't get any more black screens.

Also, I'm not sure if my PC has anything to do with the black screen, but I had to put the settings close to the lowest possible for the game to run without major lag