Mine's based on some characters I've had kicking around for a while. The characters existed first, but I'm finally writing the plot for them! Those who read my entry in the Fifth TV Tropes
Writing Contest will recognize them, as it's the wizard brothers (but in a completely different plot).
Plot: Two nations have long been, if not at war, at least full of animosity towards each other. In a lull in the anger, the king of one nation presents a gift to a powerful senator of the other. The problem: The "gift" was the king's son as a slave. While the senator is willing to accept the slave (and treat him well), his daughter and the slave-prince don't agree. They run off together, causing the tension between the two nations to erupt into a full-blown war. Ooops.
Many years later, the Senator, now disgraced and destitute, wanders into the forest of The Fair Folk
hoping they will take him and help him to die a peaceful death.
Instead, he's rescued by a boy claiming to be his grandson, and he discovers that his daughter and the slave-prince have since married and started a very unusual family—they have fifteen sons who are all part monster in some fashion. The sons, upon learning what have become of the two nations, realize that they represent all three nations: The two warring nations and the realm of The Fair Folk
. Thus, they believe it is their destiny to reunite the two kingdoms and stop the war.
Of course, it won't be as simple as that, and when you've Jumped at the Call
, your enthusiasm is bound to get you...