**Chapter 1: The Fateful Voyage**

The sun was setting over the horizon as the ship carrying Iduna, Queen of Arendelle, and her husband, Agnarr, sailed through the choppy waters of the fjord. Iduna stood at the bow of the ship, her brown hair styled in a coronet braid, her eyes fixed on the horizon. She was a woman of great strength and courage, and she had always been drawn to the sea. Agnarr, her loving husband and king, stood beside her, his arm around her shoulders. Their loyal crew bustled about the ship, busy with the day's tasks. The sound of gulls crying and the creaking of the ship's wooden hull filled the air. Iduna felt a sense of peace wash over her as she gazed out at the endless expanse of water. She was on her way to Ahtohallan, the mystical river that flowed through the heart of Arendelle, to seek guidance and wisdom. As the sun dipped below the horizon, Iduna turned to Agnarr and smiled. "I'm so glad we're doing this, my love," she said, her voice carried away by the wind. "I feel like I need to reconnect with the natural world." Agnarr smiled back, his eyes crinkling at the corners. "I'm glad we can do this together, my dear," he said. "We'll face whatever challenges come our way, side by side." Iduna nodded, feeling a sense of gratitude towards her husband. She knew that Agnarr was a just and fair ruler, loved by his people, and she was proud to stand by his side. As the night wore on, the crew settled in for the long journey ahead. Iduna and Agnarr retired to their quarters, tired but content. They knew that the journey to Ahtohallan would be long and arduous, but they were ready for whatever lay ahead. Back in Arendelle, their daughters, Elsa and Anna, were waiting anxiously for their parents' return. They were young and vibrant, with Elsa's icy powers and Anna's sunny disposition making them a formidable team. They loved their parents dearly and were eager to hear all about their journey. As the ship sailed on, Iduna and Agnarr slept soundly, lulled by the motion of the waves. But little did they know, their journey was about to take a dramatic turn, one that would change their lives forever. The sea was calm and peaceful, but Iduna couldn't shake off the feeling that something was off. She woke up in the middle of the night, her heart racing, and looked around the dark cabin. Agnarr was still asleep, but she could sense that something was wrong. She tried to brush it off, but the feeling only intensified as the night wore on. Suddenly, a loud crash echoed through the ship, and Iduna's heart sank. She rushed out of the cabin to see that a massive storm was brewing, with waves crashing against the ship and lightning illuminating the dark sky. "Agnaarr!" she cried out, her voice lost in the wind. But it was too late. The storm had already taken hold, and the ship was being tossed about like a toy. Iduna was thrown to the deck, and as she looked up, she saw Agnarr struggling to keep his footing. In a split second, Iduna knew that her husband was going to sacrifice himself to save her. She screamed his name, but it was too late. Agnarr pushed her onto a piece of debris, and with a final glance, he disappeared into the depths of the sea. Iduna clung to the debris, her heart shattered into a million pieces. She was alone, adrift in the middle of the ocean, with no sign of Agnarr or the ship. The storm raged on, but Iduna was numb, her mind reeling with grief and shock. As the sun began to rise, Iduna looked around, taking stock of her surroundings. She was surrounded by wreckage, and the sea was calm once again. But her heart was heavy, and she knew that her life would never be the same again.