1 - Establishing shot of a teenage couple, Vanessa and Troy, walking along a stone bridge (the type with waist-high walls on either side) in the woods. They are holding hands and sharing lovey dovey smiles. Troy helps Vanessa up onto one of the stone bridge's walls.
TROY: Remember when we were kids and we'd come out here to play hide and seek?
2 - Vanessa walks along the bridge wall, holding Troy's hand (more for the sake of holding it than out of necessity). She looks down at him and he up at her. She might hold her opposite arm out for balance.
VANESSA: I remember that whenever I was it you would all sneak home.
3 - Focus on Vanessa, who after going a bit off-balance, has let go of Troy's hand and flailed her arms out to help stabilize herself. She ends up leaning over the side of the bridge and looking down. Her expression changes to a mix of puzzlement and shock.
VANESSA: I'd look for ages, but I'd never find any...
4 - Focus on Troy. He kept walking while Vanessa caught her balance and has gotten a bit ahead of her. He stops and looks up at her over his shoulder, the same lovey dovey smile on his face. Vanessa has completely regained her balance and stands straight. She's still looking down over the side of the bridge, but perhaps frame the panel so we don't see her upper body (due to focusing on Troy and Vanessa being higher up).
5 - Switch to a bird's eye view, looking down on the bridge and the couple. Vanessa is still looking over the side of the bridge; Troy has turned around completely to look at Vanessa, his smile replaced with a look of concern. The riverbed below is dried up, devoid of water. However, there are some legs lying in the riverbed, coming from underneath the bridge itself (which presumably hides the body's upper-half).
TROY: Everything okay?