Diving into "Into the Deep," we're enticed by the premise of stormy passions and psychological warfare set against the vast expanse of the ocean—a setting ripe for narrative twists and emotive depth. Against this backdrop, the movie centers on a turbulent encounter among three characters: Jess, Ben, and Lexie, each bringing their emotional luggage aboard a vessel of deceit.

It's easy to get hooked initially by the seductive lure of a spontaneous romance unfolding on the high seas. Ben's charm and Jess' seeming receptivity play a well-aged trope that glitters with potential. Even Lexie's interruption, the classic third-wheel catalyst, primes us for a tantalizing tale of tension and terror.

The filmmakers aim to rock the boat not only with literal waves but with psychological undulations, as implied by the film's description. Yet, as the narrative sails on, we watch in bewilderment as the characters seemingly throw the navigation chart overboard, allowing for bad decision after bad decision.

The voyage into irrationality begins subtly. The trio starts off with intoxicating chemistry, fueled by alcohol, as they begin 'playful' games. The sexy sheen of the scenario, however, quickly tarnishes when the games spiral into a nightmarish struggle for survival. It is here that "Into the Deep" starts to flounder, drifting into the murky depths of implausibility.

Character motivations, so pivotal in a psychological thriller, seem as unanchored as their vessel. As the storyline unfolds, the audience is expected to ride along with increasingly erratic behavior, detracting from any sensible plot progression. The tension, rather than mounting with the stakes, dissipates into confusion. What remains is a frustrating specter of what could have been had the decisions made by Ben and Lexie possessed a firmer grasp on logic—or at least on human psychology.

It's not that the turns are unexpected, but that they are unearned—neither grounded in the established reality nor cleverly foreshadowed to give that gratifying 'ah-ha' moment. Instead, the film's climax feels less explosive and more like a belated attempt to detonate a wet firework. Jess, our would-be heroine, is left at the mercy of a pivotal choice that seems as though it should define her character but ends up merely as another head-scratcher.

The cast does what it can with the material, occasionally glimmering with potential under the sun of their committed performances. The ocean, a vast and beautiful metaphor for the human psyche's depths, provides a captivating canvas. However, even these aesthetic elements cannot fully salvage the wreckage wrought by the plot's dubious course.

In wrapping up, "Into the Deep" scores an even keel of 5 out of 10. It's not a dull journey—there are moments where you can almost taste the salty air of gripping drama. Yet as the end credits roll, you might find yourself wishing the characters' life preservers were stocked with a bit more common sense. It's a middle-of-the-road voyage, not entirely unpleasant but certainly lacking in the navigational prowess to make it to the destination it had charted from the start.