‘Justice League’ director Joss Whedon’s controversial, ‘toxic’ history

The opening was straight out of every old horror movie: Teen couple sneaks into a darkened building. Ominous background music swells. He wants to go up to the roof and make out. She thinks she hears a noise; he says it’s nothing. 

And then she turns into a monster and pounces on him.  “Welcome to the Hellmouth,” the 1997 pilot episode of “Buffy the Vampire Slayer,” wore its trope-flipping female empowerment on its sleeve, and audiences devoured it.