On the quiet stretch of the River Walk, Marisol paused beneath the cracked tile sign of the old café. The neon fish flickered—off, on, off—like a heartbeat skipping. She checked the folded note tucked under the planter: Meet where the water remembers. Last week, every clue had pointed here at midnight, but tonight the clock in the church tower chimed eleven and a breeze carried the smell of wet limestone. A duck startled, and a silver charm clinked against the railing, tied with blue thread—the same thread from the missing bracelets. Footprints, small and fresh, led toward the stone steps descending to the tour boats. Marisol hesitated, then noticed the tour schedule board had been flipped backward, hiding its face. Someone was here, watching. still.

Based on the mystery genre and the clues in the excerpt, what is most likely to happen next?

The river ran glassy between canyon walls, but Mateo's paddle dipped into a current that felt faster than it looked. Dark clouds stacked behind the mesa like folded blankets, and a low grumble rolled downstream. Their guide tapped the bow with his paddle twice—the signal Mateo had learned meant pull out soon. Up ahead, the canyon narrowed to a slot where boulders funneled water into slick tongues. On the bank, a line of twigs caught high in a bush showed a muddy ring two feet above Mateo's head. "Flash floods don't ask," the guide had said that morning. A chill wind blew upriver, carrying the scent of dust and wet mesquite. Somewhere, a single raindrop pocked the smooth water, then another. Guide lifted his paddle.

Based on the adventure genre and the foreshadowing, what is the most likely next step for the group in Big Bend?