A better title for the third film in the “Cabin Fever” franchise would be “Cabin Fever: Lens Flares Gone Wild.”

Instead, we’re left with “Cabin Fever: Patient Zero,” an equally apt name for a movie that can’t justify the franchise’s purpose. It even fails to stoke our fears in the wake of new Ebola virus headlines. Instead, it packs a few gore-friendly sequences but can’t rally much in the way of scares or suspense.

The film, out Sept. 2 on Blu-ray, smartly opens with a dual narrative. We meet Patient Zero (Sean Astin), held captive by scientists eager to learn why he hasn’t succumbed to the disease we’ve seen devour people in the previous films.

 

Meanwhile, a group of pals head to the Dominican Republic for a bachelor party thrown by the groom’s jock brother. We get the boilerplate characters, the sensitive soul, the musclebound jerk, the stoner and the girl who can’t seem to find enough clothes to wear..

Is it that hard to stir the horror movie formula, even just a little? Later, one of the revelers asks for a “brewski,” as if the film came out at the end of the Clinton administration, not 2014.

Of course, horror junkies don’t demand Aaron Sorkin-style dialogue. Bring the gore, the kills and the unexpected shocks. Two-thirds in, the genre goodie bag opens up. Some solid, and by solid we mean revolting, practical effects splatter the screen. Better, the dialogue takes a tongue in cheek turn that should have happened after the opening credits rolled.

And, yes, the body count starts to rise. It’s still not enough, especially when the weak finale douses our hopes for a bloody finale.

The first two films hinged on the work of serious horror auteurs. Eli Roth’s directorial debut came with 2002’s “Cabin Fever,” a flawed but fun story soaked with genre love. The talented Ti West shot 2009’s “Cabin Fever 2: Spring Fever,” but he lost creative control and did all he could to disown it.

It’s possible “Patient Zero” director Kaare Andrews, best known for his work on Marvel Comics, will go on to establish his own horror movie bona fides. He hasn’t done it with “Cabin Fever: Patient Zero,” a film that wears its flaws on its Blu-ray sleeve.

DID YOU KNOW: Eli Roth, who jump started the franchise with the original “Cabin Fever,” wrote part of that film’s script while serving as a PA on the Howard Stern movie “Private Parts.”