The giants that young teenager Barbara Thorson (Madison Wolfe) claims to kill in I Kill Giants are almost certainly not real, but for most of its running time, the movie remains successfully ambiguous about the nature of the creatures that Barbara believes are a threat to her small Long Island town. Sullen and apparently friendless, Barbara spends her time researching the history and nature of giants, concocting her own potions to use as giant bait, and planning ways to kill the evil beings intent on wreaking havoc in her peaceful community. To everyone around her, including her harried older sister Karen (Imogen Poots), who takes care of Barbara and her brother in the absence of any parents, Barbara is a troubled weirdo with an overactive imagination.
But while Karen does her best to hold the family together, two other people take an interest in Barbara and her fantasies, attempting to reach past her tough exterior. Fellow teen Sophia (Sydney Wade) has just moved in next door to Barbara all the way from England, and she’s determined to make Barbara her first friend in a new town. And school counselor Mrs. Mollé (Zoe Saldana) is equally determined to bring Barbara out of her shell and discover the root of her strange, obsessive behavior. Barbara warms to both of them in spite of herself, but she never wavers in her determination to seek out and destroy giants, even at great risk to her own physical safety.
Especially in Barbara’s relationship with Sophia, Giants has some strong coming-of-age material, and Wolfe and Wade both give very good performances, building a believable friendship between the two fragile young girls. Poots and Saldana are left with less to do as the adult authority figures in Barbara’s life, but they make the most of their few brief moments of emotional vulnerability. The story’s fantasy elements are a bit underdeveloped, and a short paper-cutout-style animated sequence detailing the history and types of giants provides just enough enticement to end up a disappointment when it doesn’t last longer.
By the time Barbara finally confronts the giants, though, the movie has shifted into a full-on maudlin tearjerker, revealing itself as a slightly more low-key take on the same material as 2016’s sappy, manipulative A Monster Calls. Giants has more grit than J.A. Bayona’s movie about a boy and the tree monster who teaches him about grief, but it ultimately ends up in the same overwrought territory, trading ambiguity for heavy-handed life lessons and a belabored twist.
Director Anders Walter, making his feature debut, keeps the giants in the shadows just long enough, and when he reveals them, they look suitably imposing, with impressive special effects for a small-scale movie. But the script by Joe Kelly (based on Kelly’s graphic novel with artist J.M. Ken Niimura) oversimplifies what should be a sense of awe and wonder, and by the time Barbara’s problems are revealed to be far more mundane than fantastical, the movie has lost all its magic.