This year at the annual Autumn Equinox Festival, Ben and his classmates determine to follow the floating paper lanterns down the river to see if the legend is true--that they soar off the water into the Milky Way and become stars. To ensure that they succeed, the friends make a pact that none of them will turn for home or look back, but of course that pact is broken soon enough, until all but Ben and Nathaniel, the weird kid, are left, traveling farther down the river than anyone has ever gone.