She was struck by the juxtaposition of the attractive, mature-looking teen and her room with its toy-themed bedding, mountains of stuffed animals, and posters of boy bands on the walls. Puberty had fallen on this home like a thunderbolt, and both the girl’s mother and the decor had yet to catch up.

Searching the girl’s closet, she felt some foil packets hidden inside the toe of a high-top sneaker. Audrey withdrew the hidden contraband: a daisy chain of condoms. She returned the prophylactics to their hiding place, not wanting to shame the girl in front of her mother in a way that would only lead to higher-risk behavior down the line.

Audrey eventually made her way to the girl’s dresser, squeezing each sock until she found a long, striped one that contained a marijuana pipe. Though Audrey had no reason to suspect that the girl had been poisoned by smoking cannabis, it offered two key insights. First, she had been lying about her innocence regarding illegal substances. Second, Audrey knew that people who trafficked in contraband typically didn’t limit themselves to one variety.

Audrey returned to the living room and presented the pipe to the girl.

“What is that!” the mother interjected.

Audrey ignored the woman, keeping her laser focus on the girl, who trembled with fear. “Who do you get your marijuana from?” Audrey asked.

The girl required little coaxing before she gave up the name of an older boy at her school: Johnny Chu.

“Has Johnny ever given you rhino horn?” the inspector pressed.

The girl glanced at her mother in shame, then nodded.

Johnny Chu lived in the New Territories, as Kowloon West was commonly known. He was nineteen and had recently moved out of his parents’ home with money he had made supplying party pills to his friends. He was new enough to the drug game, and a small enough player, that he had managed to stay off the Hong Kong Police Department’s radar.

On this night, as on many others, Johnny’s apartment was packed with sexy young Hong Kong hipsters who had come to his house party-cum-speakeasy. Dressed in gaudy designer threads, he popped a bottle of champagne, which was flypaper to the young girls dancing in his living room. As Johnny filled their champagne flutes, his eyes fell on one of the skinny teenage girls, whose body sparkled with sweat in the strobing lights he had set up to give his apartment a dance club atmosphere.

He set down the bottle of champagne and pulled a small plastic bag from his pocket. The girl noticed a dragon stamp on the packet as Johnny pinched out some white powder and sprinkled it in her glass.