The Mystery of Mermaid Bay

At grandma's for the entire vacation. What a bore! Tea on the veranda with pancakes and trips to the beach - that's great, of course. But in the seaside town, there are no familiar entertainments! There's nothing to post on social media. Suddenly, a painting disappears from the local museum. But who could possibly think of robbing a museum where the most valuable exhibits are an ancient fishing net and a life-worn piano? Yana's grandmother, the museum director, comes under suspicion. Everything points to the fact that the painting was stolen intentionally. After all, it's not just a canvas. It's a map. And for some reason, all paths lead to Mermaid Bay. All that's left is to prove grandma's innocence... and we must hurry before the vacation ends!