When Gemma Tarlach watches "Jaws," she roots for the shark.

"I’m fascinated by the villains," said the journalist and author. "Not the psychopathic villains or the sadistic villains. I mean, The Joker in ‘Dark Knight?’ Whatever."

Rather, Tarlach – a former pop music critic for The Milwaukee Journal Sentinel – is captivated by the subtle nuances of the personalities that earn society’s contempt and excommunication. This may explain why Marcus, the protagonist of her recent novel "Plaguewalker," has a day job as the scharfrichter (executioner) of a small Bavarian town and moonlights as a pimp.

"I’m really fascinated by people you think are evil," she said. "(People say) ‘To do that, you must be an evil person.’ Well, really? What does he (Marcus) think about his job? What goes through his mind as he’s torturing someone?"  

In doing that, Tarlach has produced a brilliant debut novel chronicling Marcus’ struggle to find his runaway daughter as the Black Plague ravages the German countryside.

"Plaguewalker," published by Grunaskhan Books, is a grim, compelling novel that features a backwards monomyth: it begins with death and ends with life. And in between, it is an intriguing study of humanity and compassion in the midst of a savage environment.

"It’s the anti-‘Princess Diaries,’" said Tarlach’s friend and fellow author Paul McComas. "I find it a very moving book – a book that ends on a positive note but takes a while to get there and earns that good feeling through hellish circumstances at the outset."

The book is told from Marcus’ first-person perspective and begins with a bold declaration: "I was born of the Devil. That is what they said. I was a conjure of night and fog, and the grave was the womb from which I emerged."

At the outset, Marcus is a man practical to the point of hard-heartedness. He carries on the profession of his cruel, deceased foster father; as the scharfrichter he is banned from the town proper and restricted to certain streets, unwelcome in the marketplace for fear that he would "sour the milk, or spoil the meats."

Paid to extract confessions from the condemned and to see that justice is carried out through public executions, he is a feared, shunned and disdained figure of society – a macabre walking reminder of death.

Tarlach came up with the character years ago as a disoriented new graduate student in Madison. Alone in her apartment with unpacked boxes and her dogs, she began to flip through channels on the TV and came upon a WWE wrestling show.

"One of the wrestlers came out, and I saw him and I saw the crowd’s reaction – his name is The Undertaker – and I was fascinated," she recalled. "He was very grim and he just kind of did his job, didn’t grandstand, no macho. And the crowd cheered, but they were still afraid of him."

She was reminded of her days working as a chambermaid in Germany, just out of college. At the time, she attended dual museum exhibits on crime and punishment in medieval Germany and the Plague, respectively.

"The executioner in medieval Germany, he was feared, he was ostracized, but he was also thought of as this like mystic," she said. "As I was watching this show, I just heard a voice in my head say, ‘I was born of the Devil. That is what they say.’ And it was ‘Boom, okay, I think I’ve got it.’ And it all just flowed from there."

In addition to being an executioner, Marcus is an entertainer. Giant crowds attend the beheading of a young mother (over which he presides) in the novel’s first pages. He remarks sagely to the reader that "I think the crowd learns little of respect for the law … Likely they line the alleyways to give their throats a stretch, to shout words that would be deemed profane in another circumstance."

Because Marcus is a damned soul, he is also the medium through which the townspeople indulge their most unseemly appetites. He lives with five women on the outskirts of town; two of them are prostitutes. He also has uncommon knowledge of healing herbs and medicines, so the citizens make the grim pilgrimage to the executioner’s house to offer payment in return for healing.

One of the prostitutes bore his child, Sabine, who is now a teenager attempting unsuccessfully to win Marcus’ notice. Frustrated, she runs away, and he is not initially interested in looking for her.

"I wanted to take him to a point where he started to develop the capacity to feel like a normal human and to react like a normal human," said Tarlach. "It’s not that he’s lost his moral compass – it’s that he never had it installed."

The status quo of Marcus’ existence is disturbed when the Plague is brought to town by an ominous religious order known as the Brethren of the Cross. And now, for the first time, Marcus loses his monopoly on death.

"The driving force of Marcus is that he’s an extremely practical man," said Tarlach. "I don’t think it’s until his daughter runs away and his world is completely upended that he sits and starts to think, ‘Well, what do I have? I don’t have anyone left to kill or torture, I don’t have a livelihood, I don’t have anyone to bake my bread, I don’t have anything’ – and then he starts to think, ‘Well, yeah, I do have my daughter.’" 

Tarlach recently returned to live in Milwaukee after spending some time living in Norway, and she's taking part in a series of events to promote the novel around Halloween. "In case you couldn’t tell, it’s my favorite holiday," she said.

On Oct. 26 Tarlach will appear at Boswell Books, 2559 N. Downer Ave., at 7 p.m. to read from the book. On the Oct. 27 she will appear with McComas - who'll be reading from his 2012 Midwest Book Awards Silver Prize-winning collection "Unforgettable: Harrowing Futures, Horrors, & (Dark) Humor" - at 2 p.m. at the Wauwatosa Public Library, 7635 W. North Ave.