The slasher is a time-honoured horror tradition. Alfred Hitchcock’s Psycho set the groundwork. Decades later, directors like John Carpenter and Wes Craven helped ,set the bar. Since then, the genre has seen parodies, meta films and countless new masked killers. Good slashers understand the formula and make it their own. Some filmmakers think it’s enough to have gory, inventive kills, but fans want more than that. Forging connections with the characters, no matter how superficial, and giving a story some well-constructed suspense go a long way. River is the latest genre entry from a filmmaker (Joshua Giuliano) who gets it.

After a long absence, estranged sisters, Carla (Jessica Rothe) and Lucy (Jane Levy), and their younger brother, Drew (Max Mattern), reunite to say goodbye to their deceased father. Carla left and never looked back, while her siblings remained in spite of the abuse. Regardless of the bad memories, there’s a duty to uphold. After a night of memorializing him with alcohol, they take the boat out in the morning to scatter his ashes. However, they’re completely unaware that a serial killer (Dane DiLiegro) has been dispatching victims along the same river. When their boat stalls in the middle of nowhere, they’re sitting ducks. It’s not long before the masked man sets his sights on the helpless family.

The beginning of the film is exceptionally well-conceived and executed. Where many slasher movies immediately deliver a grisly murder, writer-director Giuliano takes a different, more evocative approach. The audio of the first kill is played over shots of the crime scene. It’s like listening to a radio play with accompanying scenery to help the spark audience’s imagination. The effect is far more disturbing than watching a gruesome murder unfold. There’s a thrilling element of the unknown since this is viewers’ first introduction to the killer. It also plays into the idea that what someone envisions is probably more terrifying than anything filmmakers could show them.

In a genre with so many entries, originality is difficult to come by. However, River’s masked killer is unique. He wears an unusual mask that strikes fear in victims and perhaps even audiences. It’s a throwback to Leatherface, but more refined. His yellow swim trunks reveal his muscular form, while his half-naked body caked in blood and dirt is menacing. The siblings’ first encounter with him is immediately alarming and culminates in a high-intensity chase. The killer is relentless and proactive in trying to bring his potential victims to shore. But, even though Drew is meek, Carla and Lucy aren’t giving up without a fight. Meanwhile, their little brother finds other ways to contribute and steps up when needed.

Giuliano uses slasher tropes to explore the siblings’ bond. Audiences know there’s a serial killer stalking the river bank. But the first part of the film is more concerned with the sisters and brother’s relationship. It wants viewers to get to know the siblings. By the time they have to put their conflicts aside and band together to survive, audiences already understand their connection and weaknesses. As most horror enthusiasts know, character development is key — one needs to care about the people getting killed for their deaths to have an impact. As a result, audiences are more likely to root for the would-be victims rather than the killer.

Both Rothe and Levy are genre veterans, bringing the right tone of scared but powerful to the narrative. These are not women who will easily submit to their deaths, fighting to join the prestigious “final girl” club. The result is a tight and tense slasher worthy of the beloved subgenre.

River premiered at TIFF 2026 on September 10 and has an additional screening on September 18.

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