When Cara Rutledge rents out her quaint beach house on Isle of Palms to Heather Wyatt for the entire summer, it's a win-win by any standard: Cara's generating income necessary to keep her husband Brett's ecotourism boat business afloat, and anxiety-prone Heather, a young artist who's been given a commission to paint shorebirds for postage stamps, has a quiet space in which to work and tend to her pet canaries uninterrupted. It isn't long, however,...