Baccano! (which translates to "ruckus" or "stupid commotion") focuses on the stories of different characters in the Prohibition Era of America. Originating back to 1711, a group of alchemists seeking eternal youth are given a special potion by a mysterious demon, making them immortal. However, alchemists began disappearing, and realizing the danger of being close to one another they scatter around the world.
Now in the 1930's, all of the immortals have come together once again. Baccano! tells the stories of each of these immortals, ranging from alchemists, street gangs, thieves, FBI agents and even the mafia.
[Source: Absolute Anime]