Complex sentence: Rikki Chadwick, Emma Gilbert, and Cleo Sertori are three teenage Australian girls who find themselves stranded on the mysterious Mako Island, where they end up in a pool under a dormant volcano just as a full moon passes overhead, bathing the pool in light.
Split into simpler sentences: Rikki Chadwick, Emma Gilbert, and Cleo Sertori are three teenage Australian girls who find themselves stranded on the mysterious Mako Island. They eventually find themselves in a pool under a dormant volcano just as a full moon passes overhead, bathing the pool in light.