Coming in at a whopping $14 million in the box office, The Mortal Instruments may seem like just another high-strung teenage flop, and mostly it is. Fortunately, as someone who has read the hit book series by Cassandra Clare, upon which this movie is based, I can tell you that it may be worth the $1 you can spend at your local Redbox.

Like Twilight, The Mortal Instruments is set in the genre of urban fantasy, but with a cool, almost Roman twist. Shadowhunters, as they are called, are sent to fight demons with their angelic swords and rune tattoos, which give them superhuman abilities. They co-exist with Downworlders, who consist of the basics: warlocks, fairies, vampires, and werewolves – but no zombies.

This story focuses around Clary Fray (Lily Collins), an ordinary girl, who happens to see these Shadow hunters in action, killing someone in a night club on her birthday – but here’s the catch. She is the only one who can see them. Clary realizes that she herself is one of these sword-wielding, Latin-speaking Shadow hunters. She discovers that even her mother is not what she seems. Clary and her best friend Simon (Robert Sheehan) are dragged into the mythical world that coincides with their own.

As with the books, this movie is adequately humorous and not at all cheesy – at least, if you totally ignore the two main characters, Clary and Jace (Jamie Campbell Bower), who embody the Edward-Bella-tragic-love-from-two-different-worlds-we’ve-heard-it-all-before-kind-of story. They feel an instant attraction, throw themselves into unneeded danger, and generally make a mess of things, all for the sake of romance. What’s not to love?

The story really lies with the side characters. Simon is the typical geeky best friend who gets dumped for the demon-hunting hotrod, but his sarcastic wit and normal behavior make the Jace-Clary relationship bearable and remind us that yes, real human beings still exist.

Magnus (Godfrey Gao) is really the best written character in the whole series, though he only gets a minor highlight in this first movie installation. The High Warlock of Brooklyn, Magnus is flamboyant, witty, and mainly spends his days saving the Shadowhunters when they get themselves into too much trouble. He is also one of the only openly bisexual characters in contemporary teen fiction.

What did the movie get wrong? The list could go on for a while, but the main issues come from the fact that movie makers never seem to know when to just leave a good thing alone. Take for example the villain’s hair.

In the books, Valentine (Jonathan Rhys Meyers, whom you may remember from Bend it Like Beckham) has short, military-style blonde hair, yet the creators of this film decided that dreadlock-like braids were the way to go. They had to include the typical “Oh, I forgot there were sprinklers in the garden” scene, and the Shadowhunter teacher Hodge (Jared Harris), who is supposed to be the father figure of the organization, really just becomes kind of creepy since he basically follows Clary around, watching her.

Overall, those who truly enjoyed the film were the same ones who were earnestly flipping the pages of the novels only last year. However, if you want know why Bach is bad for a demon’s ears or why magic water could be dangerous for your health, look no further. You are in for a treat.