Why do people go missing? And why moms? Little Marina wants to become a detective to find her missing mother. Meanwhile, something strange happens in Deer Village where Marina lives. Marina and her friends collect collectible unicorn figures until the most beautiful unicorn disappears. Where has it gone? Who stole it? How can kids play together when one of them is probably a thief? So Marina has to solve her first case. The Case of the Missing Unicorn.