“I love Harley, but it’s really hard for me to buy into the idea that someone who is a forensic psychiatrist, who’s that intelligent, is gonna fall for a psychopath’s basic manipulation.”

Kami Garcia tells me this at the very beginning of our chat, when I ask her how she came to be writing Joker/Harley: Criminal Sanity with artists Mico Suayan and Mike Mayhew. The DC Comics’ Black Label miniseries has its first issue out this week.

“The first thing you learn [about a psychopath],” she says, “is that the minute you walk into those rooms, you’re already assuming they’re going to try to manipulate you. It’s a given. [...] It’s part of being a psychopath.”

Joker/Harley: Criminal Sanity is a hard-boiled tale of cat and mouse in which doctor Harley Quinn tries to hunt down the Joker rather than join him; an exploration of Harley’s origin that removes the romance between the two. Garcia says that it grew out of a desire to explore the Joker’s psyche from a place of real-world forensic science.

But first, the writer says, Criminal Sanity began as a YA project.

“I wanted to do a YA Joker,” says Garcia, who is currently working on a series of YA Teen Titans novels for DC’s Books for Young Readers line. “I wanted to do a ‘making of a monster [story]. How does a regular boy turn into a serial killer? But I really wanted it to be hyper-realistic, and the more I messed around with it the more clear it became that there was no way it could be YA.”

At the same time as writing Joker/Harley: Criminal Sanity, Garcia was in the research stages of an adult serial killer novel, talking with forensic psychiatrists and behavior profilers, so she decided to smash the two ideas together for DC’s Black Label imprint. She and a consultant profiled the Joker as if his actions were those of a real serial killer, a process that informed her version of the character.

Garcia’s Joker is “highly, highly intelligent,” a true narcissist, and completely sane.

Serial killers with hallucinations or delusions might kill for what they believe is a last resort of self-defense, she pointed out, describing the example of Richard Chase, who believed that he would die if he didn’t consume the blood and organs of his victims.

“That was completely rational to him. It doesn’t make me sympathetic to him, but it’s super sad. It’s not as terrifying as a guy who wakes up in the morning and sharpens his knives and just thinks ‘What do I want to hunt today?’ Someone who is doing this because he wants to. There is no mental illness, there’s no medication that could make the voices go away. This is how he is wired, and this is his art; this is the thing he does best [...] To me, making [the Joker] as real as possible, and sane, was the best way to make him even more terrifying.”

This Joker has a match, however, in Harleen Quinzel, expert behavior profiler. Garcia’s Harley is still a survivor of trauma and a genius doctor, and she considers it much more likely that the Joker would be attracted to her, rather than the other way around.

“He would be fascinated with her because she is fascinated with his case. [...] He would want to know ‘What does she know about me? What does she think about me? What has she come up with?’ To a true narcissist, everything is about them, so anybody who is interested in them, hunting them, following them, studying them, writing a book about them, they’re totally into it.”

Joker/Harley: Criminal Sanity #1 is on shelves now, with Harley picking up the investigation of her life: A new, expert killer appears in Gotham City, one who may have some ties to the unsolved murder of her old roommate.