"The Passenger," by Kirsten Tranter, in Sydney Noir, edited by John Dale, Akashic Press, 2019.
The publisher sent me an advance proof of this book which opens with a pastiche of, or homage to, a well-known crime novel. It's a very clever piece of work.
Robert has just arrived home after years overseas. He reluctantly attends a birthday party for an acquaintance named Fred. The reason for his reluctance is that Fred's daughter is Robert's former lover, who cheated with, and then married, Julian, a friend of Robert's.
Fred confides that Julian has disappeared with a trace. Perhaps Robert can inquire among their mutual friends? It turns out that that bunch had been pushers and users and Robert doesn't want to get involved with them.
But he gets drawn in and discovers some terrible stuff going in. You might say that the biggest difference between this story and the book that inspired it is the question of nature versus nurture: Which is responsible for the catastrophe that has occurred?