This stylized anime tells the centuries-spanning tale of a group of alchemists who, one night in 1711, took a boat trip to the middle of the ocean in search of a demon who would provide them with an elixir of immortality, the recipe for said elixir, and the secret to ending their existence should they choose to use it. They found what they were looking for, but soon realized the dangers of staying in close proximity to each other when it was discovered that one of them had eaten another. Years down the line, the immortals once again meet up in Prohibition-era America and cause a huge ruckus, or, as the Italians say, baccano!