The Fifth Soul by Diana Denisse, a blend of supernatural mystery and emotional drama, marks a compelling entry into the world of occult fiction. The book combines rich character development, intriguing plot twists, and a uniquely dark atmospheric setting that engages readers from the outset. Denisse's narrative style weaves an intricate tapestry of themes involving fate, redemption, and the human condition through the lens of the supernatural.

The novel’s protagonist, Helena Wintour, is a refreshingly complex character, embroiled in a quest to untangle her murky past while confronting the enigmatic presence of the titular 'Fifth Soul.' Helena’s journey, fraught with psychological and spiritual challenges, is etched against the backdrop of the gloomy English moors—an almost Brontëan setting that enhances the gothic undertone of the story. As Helena delves deeper into the supernatural realm, her internal battles and the malevolent forces she faces are portrayed with a psychological depth that is both haunting and poignant.

Denisse’s storytelling prowess shines in her ability to craft a world where the supernatural is believably intertwined with the mundane. The author uses a meticulous style, ensuring each scene is laden with enough suspense and detail to keep readers on the edge of their seats. The pacing of the novel is deliberate, much like the slow unfurling of a dark bloom, which perfectly suits the narrative’s tense atmosphere and the complexity of its themes.

Supporting characters in The Fifth Soul are equally well-crafted. From the enigmatic Mr. Grayson, whose motives are as obscure as his past, to Maria, a childhood friend of Helena with secrets of her own, each character adds layers to the story, providing both allies and antagonists for Helena. Their interactions with the protagonist are not only pivotal in driving the plot but also provide deeper insights into Helena’s character, making her journey not just a solitary fight against darkness but a multifaceted battle involving those she holds dear.

One of the standout elements of the book is its dialogue. Denisse channels authentic voices for each character, which resonate with their distinct backgrounds and personalities. Dialogue in supernatural novels can often feel stilted or unnatural, but here it flows seamlessly, offering readers both clarity and depth. The vernacular used not only helps in fleshing out characters but also in building the dark and eerie world they inhabit.

Thematically, The Fifth Soul does not shy away from exploring deep and occasionally disturbing issues. Denisse addresses the concept of the soul and its purity, the impact of past sins on the present, and the redemption arc in a manner that is both philosophical and accessible. The supernatural elements, while central to the plot, do not overpower these themes but rather serve to highlight them, allowing the reader to ponder the existential questions posed by the book.

However, the book is not without its shortcomings. At times, the meticulous attention to detail in scene setting may slow down the narrative, potentially leading to a pacing that might not cater to all readers. Moreover, the complexity of the plot, while generally a strength, can occasionally become convoluted, leading to moments where readers may find themselves re-reading passages to fully grasp the interconnections between characters and events.

Overall, The Fifth Soul is a robust novel that offers a spellbinding mix of suspense, emotion, and supernatural intrigue. Diana Denisse demonstrates a keen understanding of the gothic narrative form, revitalizing it with her innovative use of theme and setting. The novel not only promises a thrilling read but also invites reflection on deeper philosophical questions, making it a standout in its genre. Readers looking for a dense, thought-probing story that combines the best elements of psychological drama and supernatural mystery will find The Fifth Soul both challenging and rewarding.

In conclusion, Diana Denisse's The Fifth Soul is an evocative and meticulously crafted novel that will appeal to fans of gothic supernatural tales and those who appreciate a deep, character-driven story. Despite some minor pacing issues, it remains an impressive novel that confidently delivers a gripping tale of mystery and the supernatural, making Denisse a noteworthy author in the realm of occult fiction.