An old dog hangs around the Monarch Tavern in Justin McConnell’s Lifechanger. The pooch greets the regulars who stop by the Clinton Street drinking hole throughout this intriguing psychological thriller/body horror hybrid. At first, the dog just seems like a friendly neighbourhood mutt as he greets one of the patrons. Then he appears the next night and the following day, running up to the guests with excitement and recognition.

The dog is a subtle stroke with which McConnell gradually reveals the story behind Drew, the narrator of Lifechanger and the man who presumably owns the four-legged friend. When we first meet Drew, however, he is an attractive thirtysomething woman named Emily (played by Elitsa Bako) who wakes up beside a gnarly decomposed body. Emily seems disoriented, hazy after what looks like a one-night stand and/or bender gone wrong. Emily stumbles home and fights with her husband, who is more angry than relieved to see her return. Her skin soon becomes a little splotchy. Gray patches appear, as if her flesh is decomposing while she breathes. The sequence proves disorienting for the viewer as a male narrator speculates in the first person about the actions made by the female character.

Emily then attacks her husband ferociously. She isn’t the one being violent though. Drew is.

Drew, as he explains, must change host bodies to stay alive. He’s a shapeshifter and Lifechanger sees the character jump from actor to actor as he inhabits the physical vessels to continue his life on earth. When Drew appropriates a body, its owner dies a horrible death as he replicates himself with their physical matter. Lifechanger delivers macabre body horror as Drew’s bodies decompose and ooze milky pus, while the victims snap and writhe in excruciating agony thanks to a mix of intense physical performances by the actors and some snazzy practical effects. (The actual transition process never makes much sense but anyone looking for hard science is searching in the wrong film.)

Much changes as Drew goes through host bodies at increasingly rapid speed as they deteriorate. The range of actors playing “Drew” also keeps the dynamic lively as their physical interpretations differ from host to host. (Fortunately, the weaker players tend to host Drew for only a short time.) Drew doesn’t discriminate between men and women, but there is a predatory bent to his body’s demeanour if his host is male as the film culminates with relevant commentary on misogyny and male entitlement.

As the host bodies frequent the Monarch, greeted by the dog with each turn to provide a sense of familiarity and to show that Drew is innately good, a pattern emerges in Drew’s behaviour. Each host seems drawn to a beautiful but sad looking blonde named Julia (Lora Burke) who sits alone at the bar every night. Julia provides the emotional core of the film thanks to Burke’s compelling performance that makes the character an open, complicated observer who thrives off the same things Drew feeds on. A little flirting, a few drinks, and maybe some action pepper the nights and as Julia becomes a constant presence to the revolving door of characters inhabited by Drew. As Drew circles Julia night after night, Lifechanger’s mysterious hunter simply reveals himself a lonely soul looking for connection.

Lifechanger keeps audiences guessing with the enigmatic shapeshifter at its core. McConnell crafts an intriguing interplay between showing and telling as the Drew’s rambling voiceover challenges the viewer to interpret the credibility of his words in contrast to his actions. (The sound design, a bit too busy, demands active listening.) The tone of his transitions becomes less sinister and devilish with each attack. Drew kills not for pleasure, but for necessity. Bill Oberst, Jr. provides the narration throughout the film as Drew swaps bodies and his deep voiceover provides a source of consistency as the film increasingly challenges audiences to understand and empathize with this chameleon killer. The more Drew reveals about himself, the more one finds mitigating factors for his defense. As both a character study and an exercise in low-budget genre filmmaking, Lifechanger finds a smart balance between the ideas it seeks to evoke and the unsettling thrill that horror provides while withholding information from the audience.