You shall carry your sibling, be his support and guide.
He shall be your shelter, guardian, aegis firm.
United you stand, divided you fall.
Brendan stared at the creature in the pale moonlight, transfixed by the silvery petals that glistened beneath that perfect purity. It was not until his final breath that he gathered his wits enough to scream after the thing had descended on him, all muscle and thorns and hard, barklike skin. It was too impossible, even the crimson blossoms that shone in the light of the moon.
The player characters, experienced and somewhat well known, hear rumors and travelers' tales about a distant area being overrun by dragons (or other terrifying monstrosities). The locals have sent them a message, begging for heroic aid.
When they investigate, they discover that nothing of the sort is going on. It turns out that a group of thieves wanted them out of the way so that they could rob them (or someone who would normally receive their protection).