The test tone for a 5.1 system is usually just a boring voice saying, “Left front. Center. Right front. Right surround…” But Maya realized her film was her test tone. It was the most brutal, beautiful diagnostic tool imaginable. If every speaker—especially that howling, chest-punching subwoofer—told the story, she had succeeded.

It wasn't from the front. It came from the —a slithery, dry sound, like insect legs on glass, that passed behind her head and moved to the surround left . Maya’s neck prickled. She actually flinched, turning her head toward her empty kitchenette.

She navigated to the test clip. A specific sequence: the protagonist, Elara, walks down a long, circular corridor. Something is hunting her.