Rent Casshern Sins (2008 - 2009)

Casshern Sins is a Japanese animated drama series about Casshern, a mysterious assassin who wakes up to a world where the air is poison and two rival forces, humans and robots are trying to stay alive on a hostile planet. The cause of this poison was the murder of Luna, a woman Casshern may have met in his past, if only he could remember how. The series follows Casshern’s attempts to recover his elusive memory and survive on a planet that is constantly trying to kill him.