A tiny piece of paper from the year 2019 might not sound very interesting to most people. But Max and Oscar, who are Bluggsville's sharpest sleuths, aren't most people! Max has a hunch that this ancient patch of paper might be valuable and extremely rare. Max is right. This isn't just any old piece of paper. It's a strange, sticky thing called a postage stamp, and it's more than 400 years old! It's an exciting discovery, but before long, it leads Max and Oscar into some very sticky situations...