The perilous repercussions of a horrific childhood secret propel Spat the Dummy, Gemini Award–winning screenwriter Ed Macdonald’s dynamic exploration of sex, drugs, violence, and the meaning of fatherhood. This excellent debut novel combines gutsy language and a relentless, engaging plot with one of the most chaotic but loveable protagonists in recent CanLit.

Macho, resolutely heterosexual Spat Ryan is firmly established as someone who flouts every possible orthodoxy when, within the book’s first dozen pages, he gladly accepts a blowjob from his male best buddy. But as he recounts how he kick-started the second day of his honeymoon with ex-wife Patty by taking a stroll through a porn ­arcade and paying to screw an underaged teen girl in a video booth, the reader begins to perceive this rebel as deeply troubled. The fact that he spends most days baked on weed and medicated by successive double shots of gin only adds to the disquiet.

Spat was raised by a single father after his mother fled their home in Montreal with her other son, then an infant. The dramatic event that precipitated her departure has haunted Spat ever since. At age 40, he bears many scars from the abuse and neglect meted out by his extremely violent late father. When Spat learns his ex is pregnant with a baby he’s convinced is his, he ­travels the globe to reconnect with his remaining family members, face his demons, and begin a halting trek toward sobriety.

Spat’s gonzo journey from nihilistic addiction to redemptive grace is told in vivid and hilarious prose populated by distinct and memorable characters. The narrative twists and turns are accompanied by sophisticated thematic preoccupations, as Spat slowly transforms from a man who lives for fistfights and “vaginal proximity” to someone with the capacity to feel deep concern for his ex-wife’s newborn.

The novel possesses a few minor flaws: several superfluous dream sequences and unnecessary internal monologues, a handful of contrived philosophical conversations, and an egregious moment that encapsulates the entire story and explains Spat’s personality, which has already been amply demonstrated. But these occasional distractions are countervailed by utterly captivating storytelling. Despite some of the raw horrors it depicts, this satisfying book leaves the reader feeling grateful to be alive.