Vitrouve 2: Shadows of the Past

In the second book, the class of Nathan will travel to Saturn because that is where their species originated from but their ship will crash. After that, they have to fight through the woods, which seem to be haunted by old beings. Two of their teachers get kidnapped, and while the rest of the class wants to move on, Nathan and her friends look for them. They get separated from their class and have to find their way back to civilization despite being on a completely different planet. But when they finally arrive home, the search for Nathan's biological parents puts her in danger. They end up in the hideout of the Nameless and could get caught at any moment.