Protected by the Billionaire Ex-SEAL, authored by Ava Nichols, nestles comfortably within the romantic suspense genre, blending steamy romance with nail-biting action in a way that promises to keep readers engaged from cover to cover. Nichols, known for her strong character development and thrilling plots, does not disappoint in this latest offering, where love and danger intertwine.

The novel introduces us to Sarah Jennings, a small-town librarian with a placid life that belies her tumultuous past. Her character is well-drawn—resilient yet vulnerable, making her relatable to readers. Her world turns upside down when she unwittingly becomes entangled in a criminal conspiracy, thanks to an ancient manuscript she discovers hidden within a donated book. This manuscript not only piques her curiosity but also marks her as a target for a dangerous criminal syndicate that will stop at nothing to recover it.

Enter Jameson Hawk, the titular billionaire Ex-SEAL, whose transition from military to civilian life has been anything but smooth. Hawk sets up a high-end security firm, employing his skills to protect others, and Sarah's case becomes his top priority. Jameson Hawk is crafted with precision—a tough exterior layered over a deeply compassionate core, his protective instincts are undeniable and his prowess as a former SEAL lends credibility to the action scenes. His interest in Sarah, initially professional, soon delves into the personal, setting the stage for intense romantic developments.

The chemistry between Sarah and Jameson is palpable; Nichols excels in crafting their interactions with a blend of tenderness and tension that fans of the romance genre will find immensely satisfying. Their relationship evolves believably, with each encounter ratcheting up the stakes, making their emotional and physical connections seem inevitable and deeply right. The romance does not overshadow the suspense but enhances it, weaving seamlessly into the larger narrative of mystery and danger.

Nichols also incorporates a commendable supporting cast of characters—each adding depth to the story. From Sarah’s spirited best friend who provides comedic relief to Hawk’s fiercely loyal colleagues who aid in the quest to protect Sarah, these characters contribute layers to the plot and dynamics between the leads. It's the interactions among these characters that enrich the storyline, providing breaks in tension and insights into the protagonists’ true selves.

The plot of Protected by the Billionaire Ex-SEAL is tight and well-paced, with twists that are both surprising and plausible. Ava Nichols does an excellent job of drip-feeding clues that allow the reader to engage actively in unraveling the mystery along with the characters. The settings—from the quiet library to the lavish security headquarters and the shadowy places where the antagonists lurk—are described with enough detail to be vivid but not verbose, creating a backdrop that complements the story's mood perfectly.

However, while the novel is a compelling read, it does not escape certain clichés typical of the genre. The trope of the damsel in distress being rescued by a knight in tarnished armor is familiar ground, and though Nichols attempts to instill agency in Sarah, there are parts where she inevitably falls into typical victim patterns. Nevertheless, the self-awareness in the writing and the occasional flipping of these clichés add a modern touch to the narrative.

The conclusion of the book is particularly strong, offering a satisfying resolution to the suspense while leaving room for potential sequels—something that fans will no doubt appreciate. Nichols ties up the threads of the story convincingly, delivering emotional payoff and justice in equal measure.

In summation, Protected by the Billionaire Ex-SEAL by Ava Nichols is a recommended pick for those who enjoy romantic suspense with strong characters, tangible chemistry, and a healthy dose of action. While navigating some predictable territory, the novel ultimately provides an exciting and heartwarming escape into a world where love might just be the most powerful weapon against darkness.