Lucky the Mermicorn and the entire Fin-tastic Four are getting ready for a delicious new challenge! They are entering a very special baking competition alongside their brand new undersea best friend, Nelia the Narwhal. Ruby is absolutely determined to win the top prize, and Lucky wants nothing more than to help her achieve her dream. Armed with a treasure trove of magical seashells and his very important mission to share the magic, Lucky plans to make Ruby's sugary creations the biggest and best treats Mermicorn Island has ever seen. But magic can be quite unpredictable. When things do not go exactly according to plan, Lucky suddenly finds that he might just have a massive, whale of a problem on his hooves! Join this adorable half mermaid, half unicorn hero on another sweet and exciting underwater adventure full of teamwork, fabulous pastries, and wonderful surprises.