Phantom: The Animation

Plot
The  OVA series follows Zwei as he makes a trip to America, only to witness an assassination that leads to his memory loss and indoctrination into Inferno. Though not as heavily as in the game, we see Zwei's training before he goes with Ein to help with an assassination. While a different path is taken, deceit and betrayal rip apart Inferno and place Ein and Zwei on opposite sides, which eventually leads to a climatic battle between them at the end of the anime.