Directed and co-written by Peter Thorwath, Blood Red Sky has a high concept that's immediately appealing and easy to grasp: Vampires on a plane! Mostly, Thorwath coasts on that concept during the film's long two-hour runtime; however, he does attempt to add some emotional depth to the inherently silly story. While the film does provide some solid entertainment, Blood Red Sky's silliness and pathos run thin before the movie ends.

It's not hard to figure out that single mother Nadja (Peri Baumeister) is suffering from vampirism. She hides in a darkened hotel room while her young son Elias (Carl Anton Koch) checks them in on a flight from Berlin to New York City. They're traveling to meet with a doctor who can potentially cure Nadja. The bald Nadja affixes a wig and injects herself with some kind of medication. Elias describes her affliction as something being wrong with her blood, which friendly stranger Farid (Kais Setti) interprets to mean that she has leukemia.

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Dominic Purcell in Blood Red Sky

Dealing with leukemia would probably be easier since Nadja has to carefully plan her transatlantic trip to take place on an overnight flight that allows her to experience five extra hours of nighttime, and carry medication to keep her bloodlust at bay. However, a terrorist group soon hijacks their flight, presenting an even larger threat for Nadja and Elias.

It's never quite clear what the terrorists' objectives are, and the crew is full of mostly interchangeable gruff, buff guys, led by Berg (Dominic Purcell). They plant explosives around the plane and change the flight path so they can parachute out over an undisclosed location. The closest the movie comes to explaining their motives is when several passengers speculate about vague schemes to crash the stock market by simulating a terrorist attack.

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Peri Baumeister in Blood Red Sky

But Blood Red Sky isn't Passenger 57 or some other standard airline-hijacking thriller. This is a movie about a vampire, and so of course Nadja will soon allow her inner demon loose with the noble intention of taking down the hijackers, and of course, that will all go horribly awry.

Nadja's vampiric look is like a more feral version of Nosferatu's Count Orlok. The more blood Nadja sucks, the more monstrous she becomes, and the scarier she looks. The makeup team does excellent work depicting Nadja's gradual evolution into a dangerous inhuman beast. Her battle against the hijackers is exciting at first, especially as they slowly discover what she really is while she sneaks around the plane. Alexander Scheer gives an entertainingly over-the-top performance as Eightball, the only terrorist with a personality, who seems far more interested in violence and murder for its own sake than in whatever ill-defined goal the group actually has. But his penchant for nihilistic mayhem also drives the movie's third-act turn into a zombie-movie rip-off, as the plane is eventually overrun with mindless ghouls.

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Amid the action, Thorwath aims for an emotional story about mother-son bonding, with the tender dynamic of a living child caring for an undead parent, serving as a reverse take on Let the Right One In. But Blood Red Sky can't achieve anything near the thematic resonance and sustained dread of Let the Right One In -- or even its American remake -- had. The flashback scenes depicting Nadja's vampire origin and struggles only drag the movie down.

While Blood Red Sky is undeniably ridiculous, it mostly takes itself seriously. There are a handful of campy moments, including Eightball fashioning a wooden stake out of a hockey stick; but, its overall story is straight-faced and grim. The film clumsily hints at some social commentary when the hijackers force passengers of Middle Eastern descent to pose as terrorists to throw off the authorities. There's an unnecessary framing of the story that starts at a Scottish airbase where the plane has made an emergency landing, but it doesn't add any tension or mystery.

Blood Red Sky has enough gruesome vampire action that viewers who aren't looking for anything more than that may find it sufficient. But for such a fun, attention-grabbing high-concept premise, the execution is disappointingly repetitive and dull.

Blood Red Sky premieres Friday, July 23 on Netflix.

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