Its the summer of 1941 in Middleton, Minnesota. Eleven-year-olds Mark Penn and Swede Larson have built a treehouse along the river. School is out and the boys are looking forward to the arrival of the Ringling Brothers and Barnum & Bailey Circus, the Fourth of July parade, and the baseball season of the Middleton Aces. Mark is the teams batboy and Swede a ball shagger. One day while swimming in the river, they spot the hood ornament of a submerged...