Halloween.

On the night, Los Angeles celebrates its dark side, one man's revelry turns into a nightmare.

This person wearing this costume and this hooded robe coming out of the rose bushes,

I mean, you would have thought it came out of a scary movie, but this was real life.

Did a passion for fringe interest to lead to murder?

He got into alien cultures, ancient cultures, ancient civilizations.

And he had this business where he sold spirit animal furs to adults.

One of his favorite venues, it's a Gothic S&M Club.

Police eventually discover the truth is even more frightening

than alien ancestors or S&M.

Halloween did provide a great setting for the shooter in this case to disguise his appearance.

All murders are bad, some are more heinous than others, and this was about as bad as it gets.

You think you realize where the bottom of society is, and then you realize that whatever that bar was was lower.

It's a mystery that proves on Halloween, some monsters are real.

I'm like Dr. Frankistar.

I'm sorry, it's crazy.

Most people are dressed in Halloween costumes.

People are all in masks.

West Hollywood is really the epicenter of partying on Halloween in Southern California.

Hollywood's been a Halloween party night for decades. It's a fun time, but it's also a scary time.

You have your ghosts, you have your goblins, you have your devils.

No one's thinking that the ghost or goblin, the person dressed up in those costumes,

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