Happy Birthday, Geronimo! (Geronimo Stilton #74)

When you're with Geronimo Stilton, it's always a fabumouse adventure! It was my birthday! I was out with my family and friends celebrating when I realized, someone had replaced all my money with phony bills. I couldn’t pay for my cheesecake! Could Hercule and I track down the prankster before it ruined my special day?