Many plankton journey from the cold, dark depths of our oceans to the surface, only to eventually drift down again into the darkness in a perpetual rhythm. Yet, how single-celled phytoplankton, most of which have no appendages to help them swim, make this pilgrimage has remained a mystery. Researchers now describe a species of bioluminescent phytoplankton, called Pyrocystis noctiluca, that balloons to six times their original size of a few hundred microns. This massive inflation allows the plankton to journey up to 200 meters toward the ocean's surface to capture sunlight, then sink back showcasing a unique strategy for long-distance ocean travel.