Dinoflagellates live free-floating in the ocean or symbiotically with corals, serving up — or as — lunch to a host of mollusks, tiny fish and coral species. But when conditions are wrong, dinoflagellates poison shellfish beds with red tides and abandon coral reefs to a slow, bleached death. Globally, this is happening more and more often. Seeking answers, a team of researchers sequenced the complete genome of a dinoflagellate species for the first time.