Heisenberg

Dr. Walter Hartwell "Walt" White, Ph.D., (also known by his clandestine alias, Heisenberg) is a fictional character and the protagonist of the American television drama series Breaking Bad on AMC. He is portrayed by Bryan Cranston and was created by series creator Vince Gilligan. Once a promising chemist who was one of the founding members of the fictional, now multi-billion dollar company "Gray Matter Technologies", Walter left the company for personal reasons and became an unhappy and disillusioned high school chemistry teacher. After being diagnosed with inoperable lung cancer, he resorts to manufacturing methamphetamine to ensure his family's financial security when he dies. As the series progresses, Walter gradually becomes darker and takes on a more villainous role.
Although AMC officials hesitated to cast Cranston due to his previous comedic role on Malcolm in the Middle, Gilligan cast him based on the actor's past performance in an episode of The X-Files. Cranston has contributed to much of his character, including Walter's back story, physical appearance and personality traits. Gilligan had described his goal with Walter White as turning Mr. Chips into Scarface, and has deliberately made the character less and less sympathetic.
Both the Walter White character and Bryan Cranston's performance have received critical acclaim. Cranston won three consecutive Primetime Emmy Awards for Outstanding Lead Actor in a Drama Series, becoming the second actor ever to do so and the first since Bill Cosby for I Spy in the 1960s.