Over the past decade, Breaking Bad’s Bryan Cranston has successfully made a very unlikely transition — from a goofy father of three to a former chemistry teacher who uses his scientific expertise to cook meth. In a recent interview with The Wall Street Journal, Cranston talked about first reading the Breaking Bad script and how he makes his anti-hero character so likable.

“I started reading and the first page is a pair of trousers falling from the sky over red clay dirt, an RV runs over them. And I’m going, “What? An RV? Huh?” It drives recklessly down an empty dirt road — and inside the RV, a man dressed in tighty-whitey underwear and a respirator drives frantically. Next to him is another man passed out with a respirator. Behind him are two dead men sliding up and back in a sea of chemicals and glass,” recalled Cranston. “That was the first page. It was the best drama script I’d ever read. I called my agent and said I want to meet with (creator Vince Gilligan) this week. I knew that for anyone who was lucky enough to get this role, it’s a game changer.”

It seems that Cranston’s Walter White is so endearing to audiences because of the actor’s inherent likability, not because he’s an easy subject to root for. “I don’t care about keeping him likable,” he explained. “My approach is to just keep him real… We need to know what motivates this person. We’re witnessing a metamorphosis of character, but at every step there’s a dose of humanity. Walt can kill someone one minute and lovingly caress his baby the next.”

Cranston also touched on how he came up with his Breaking Bad character’s back story. “I wrote an extensive back story for myself using the confines of what Vince has said. I came up with my own reasoning that (Walt) developed a severe panic of failing. He was a bright young man whose teachers, peers, professors and family members all told him the sky’s the limit, you can write your own ticket. If enough people tell you that it can make you vibrate a little bit in panic.”

The fourth season of Breaking Bad, which airs Sundays on AMC, began Sunday.