The old lighthouse keeper was dead on the rocky shore. Inspector Sarah Chen arrived just as the storm clouds gathered. The victim's daughter stood crying beside two uniformed police officers. Blood mixed with seawater created dark pools between the rocks. Nobody had seen Thomas Whitmore since the previous Tuesday night. His boat remained tied securely to the weather worn dock. The lighthouse beam continued its endless rotation through thick fog. Sarah noticed fresh scratches on the deceased man's weathered hands. The tide was coming in fast, threatening potential crime evidence. She had exactly thirty minutes before the scene was compromised.