Ada Ru finally thought her parents were going to agree to a Fitzhugh family vacation in Disney World the summer before sixth grade, until her father announces he's taking a teaching position in Scotland, and moving the family there for the entire summer.

Ada Ru is anything but happy. She doesn't like their new home, she hates haggis, and she certainly doesn't like the idea that she will be away from her best friend all summer. To top it all off, there is said to be a monster in the lake near their house

That's when she meets Hamish Bean Timmy, Hammy Bean for short, captain of the Nessie Quest Monster Chaser boat tour. He knows everything there is to know about the fabled Loch Ness Monster and Scotland. But as the two unlikely friends embark on an epic adventure to spot the lake monster, they end up discovering more than they ever could have imagined.