Gemma Masters is a comic book character from DC Comics / Vertigo, best known as the niece of the occult detective John Constantine. First appearing in Hellblazer #4 (1988), created by Jamie Delano and John Ridgway, she plays a recurring role in the supernatural lore of the Hellblazer series.

Key Overview

• Family Background: She is the daughter of Cheryl Constantine (John's sister) and Tony Masters. Because she belongs to the Constantine bloodline, she inherits a natural affinity for magic and the occult.

• Relationship with Magic: Growing up, Gemma was fascinated by her uncle John’s glamorous, mystical life—unaware of the danger, grief, and tragedy that constantly surrounded him. Against John's wishes, she dabbled in magic during her adolescence and early adulthood, occasionally attempting to follow in his footsteps as an occultist.

• Magical Abilities: Gemma demonstrates an aptitude for various magic practices, most notably vivimancy (the manipulation and control of living spirits, contrasted with necromancy).

• Trauma & Conflict: Like many of John Constantine's relatives and associates, Gemma's connection to him leaves her exposed to demonic forces, cults, and tragic collateral damage. Over the course of the series, her relationship with John turns complicated and bitter, as she blames him for the recurring darkness that haunts her life.

Backstory & Relationship with John Constantine

• The Constantine Curse: Gemma’s background mirrors her Vertigo/DC origin—she grew up worshipping her estranged uncle John, drawn to the mystery and pull of the occult despite his strict warnings to stay clear.

• The Fallout: Attempting to dabble in magic to carve out her own identity (and escape a chaotic home life with Cheryl and Tony), her rookie spellwork went wrong. It inadvertently exposed her family to demonic collateral, leaving her alienated from her parents and bitterly resentful toward John for bringing the supernatural darkness into their lives in the first place.

• The Break: Refusing John’s interference or "help"—which usually makes things worse—she cut ties with her family and fled.

Current Status: Life in Happy Harbor

• Turning 18 on the Streets: Having spent her late teens running, Gemma recently turned 18. She finds herself living homeless on the coastal streets and boardwalks of Happy Harbor, Rhode Island.

• Why Happy Harbor?

  • It’s far enough from London to keep a low profile from John and his demon-hunting circles.

  • Happy Harbor has a strange, quiet magical/super-heroic residual energy thanks to Mount Justice (the Team's former covert HQ) and the Justice League’s history in the area.