In a quiet coastal village, a young fisherman named Tomás lives a simple life, but he has always dreamed of adventures beyond the horizon. One day, while mending his nets on the beach, he hears a mysterious song that seems to emerge from the depths of the sea. Intrigued, he dives into the water, only to discover an ancient legend: the spirit of a beautiful mermaid trapped in a shimmering coral. Her charm is irresistible, and Tomás feels drawn to her as the mermaid shares stories of love and heartbreak, and the secrets of the ocean.
But when Tomás returns to the surface, he realizes that his daily life has begun to topple. The mermaid, named Lira, has awakened within him a longing for the unknown, and he increasingly feels distant from his life in the village and his fiancée, Elena. The struggle between duty and love becomes an internal battle, as Lira's influence leads him to risk everything.
As the village faces a series of mysterious shipwrecks, Tomás must decide whether to follow the mermaid into an uncertain future or to protect his community and the life he has always known. With each song Lira sings, the young man realizes that true love cannot always be found in the depths of the ocean, and that sometimes, the greatest sacrifice is to embrace what one already has.