Seventeen-year-old Marnie Haynes knows there’s no such thing as magic, she stopped believing the night her father told her that her mother died due to depression and not a Siren’s song.
Hmm. This starts out okay, with a middling sense of character in that we know we've got a kind of no nonsense older teenager who doesn't believe, but then things get odd. For one, can you die of depression? I mean sure, depression can lead to many lifestyle choices that can kill you, I'm sure, but depression itself can't actually be a clinical cause of death, I don't think, so it looks weird to see that in the opening line of a query (see Query Shark for an example of why you've got to get facts right).
That said, I like the Siren's song. For one thing, it's specific, and for another it hints at world, but it too feels a little off. Sirens called sailors from off their ships, but the men actually died of drowning, not bleeding from their ears. Isn't that how the legend goes?
But in the Bay of Sirens—a craggy, island deathtrap off the coast of Ireland—odd things are happening to make Marnie rethink her beliefs.
This though, I love. It's specific, it's Ireland, and even though the last clause is totally vague, you explain what things you mean right afterward.
But not everyone wants to help her. When the town’s mayor claim’s Marnie is a monster and tries to poison her, then throws her off a cliff; Marnie is left hanging onto life by the strings. Huh? What strings? She’s saved by two men—both who look like monsters, with green skin, sharp teeth,
Umm ... I think you're falling into synopsis territory here. As in, TMI. Remember, all a query need do is entice an agent to read pages. There are examples that break the rules, but usually that's done in a letter in which the meat of the query (the story summary) is two or three paragraphs of 250 words or less. The best queries convey CHARACTER (introduce us immediately to a person we can like (or at least love to hate) and sympathize with right away, and give us a sense of who they are before you show us what happens to them), CONFLICT (this is the obstacle the character must overcome in order to achieve her goals, it can be internal, it can be external, it can be realistic, or it can be fantastical, but in a query, it must be specific, interesting, and concise), and CHOICE (this I actually don't swear by quite as much. The best queries do often end with a sadistic choice, but sometimes that doesn't really fit the story. If a difficult choice to be made does fit your story, be sure to make it clear in your query, and at least imply what the consequences of failure will be).
I say this, partly, because your query is too long (the meat is 299 words, but it reads as even longer, probably because of so many paragraphs) but also because you want to really hold your reader's attention. The reason short queries usually work best is that you want to introduce a character, entice the reader with specific conflict and/or a well imagined world, and then have them chomping at the bit to get to your pages.
Her life is turned inside out when it’s revealed that she’s not crazy. Revealed to whom? And how? She’s part-Faerie and because of the mayor’s actions, a war has been started on her behalf. Now her real father, a Kelpie in the Unseelie Army, is willing to kill anyone—even her friends and family—to get his hands on her.
At this point you've gone on too long, but I will say this sounds interesting. Specificity is the spice of every good query. I love that you don't name her dad, but you do name his army, and his species. That really gets my imagination going. If you could work this kind of detail in earlier, and more succinctly, this query would be much improved.
Coerced into going with the Faeries to learn their ways, Marnie resolves to hate them. She's half Fae, half Kelpie, and zero percent human? It doesn't really matter, I suppose, but I'm curious. Always try to keep logistics in mind, and remember that your reader is going to be thinking, trying to figure out all the details. But as she grows closer to them, she realizes all is not what she thought. When the humans of the island hatch a plan to rid the place of the Faeries forever, it’s up to her to choose which side she’ll be on and who will survive the first, and maybe final, battle.
DARK HARBORS is a 80,000 word fantasy novel with contemporary elements that will appeal to fans of Maggie Stiefvater’s THE SCORPIO RACES.
This is good.
Thank you for your time.
Okay, in summary: you've got the elements here, the skeleton of a good query, so to speak. Even if Irish Faeries have been done, you've got some unique elements, and I can see enough to tell that the story in your manuscript is probably a lot of fun.
But ... you need to work on presentation here. You've got some high points, to be sure, but there's too much, and I think you need to focus on paring it down:
Marnie is no-nonsense, but must either accept magic is real or that she's crazy. (CHARACTER)
There is a war between the Kelpies and the Faeries--or is it the Kelpies and the humans? Not sure. (CONFLICT)
She must pick a side. (CHOICE)
Obviously there's more to it than that, but these are really the only three things you must convey. Present them in a cool way, and so that we care, and you'll be in great shape.
What do you all think? Anything to add?