With his game-changing crime drama Breaking Bad, Vince Gilligan famously set out to turn Mr. Chips into Scarface. After being diagnosed with lung cancer, mild-mannered chemistry teacher Walter White kickstarted an illicit career as a meth cook with one of his former students and ended up becoming the drug lord of Albuquerque.

There are a few key moments that chart Walt’s gradual transformation from a timid everyman into a reprehensible monster. By the end of the series’ groundbreaking five-season run, Walt had fully receded into his notorious Heisenberg persona.

When He Was Diagnosed With Lung Cancer

Walt sits in the doctor's office in Breaking Bad

The inciting incident in Breaking Bad is Walt’s lung cancer diagnosis. When audiences first meet Walter White, he’s just going through the motions. He has a passionless marriage, a mountain of debt, and a dead-end job he’s overqualified for.

Being diagnosed with a terminal illness and learning he has two years to live is the big life change that sets Walt on the course to unleashing his inner demons and morphing into a porkpie hat-wearing meth kingpin.

When He Stood Up To The Teenagers Bullying His Son

Walt stands up to a bully in Breaking Bad

In the pilot episode, Walt is introduced to audiences as submissive and weak. He avoids confrontation and lets people walk all over him. But that all changes when he takes Walt, Jr. shopping for clothes and a bunch of teenagers make fun of him.

When Walt stands up to the teenagers who bully his son in the clothing store, the audience gets their first glimpse at a more assertive and violent personality that will eventually manifest itself as Heisenberg.

When He Killed Krazy-8

Walt kills Krazy-8 in Breaking Bad

Walt’s killing of fellow drug dealer Krazy-8 was the first of many murders he would commit throughout the series’ run. Walt initially wants to show mercy and let Krazy-8 go, but when he realizes his prisoner has kept a shard from the plate he broke, he confronts him about it and narrowly avoids getting slashed to death. He promptly strangles Krazy-8 with a bicycle lock restraint.

Before discovering the missing shard, Walt was going to cling to his humanity by sparing Krazy-8’s life. But after being deceived and nearly killed, Walt realizes he can’t afford to have mercy in his new life as a career criminal.

When He Blew Up Tuco’s Headquarters With Fulminated Mercury

Walt holding a piece of fulminated mercury in Breaking Bad

After Tuco’s goons beat Jesse and rob his meth supply, Walt confronts Tuco at the headquarters of his operation – identifying himself as “Heisenberg” – and demands reimbursement for the stolen meth and compensation for Jesse’s pain and suffering. Tuco initially laughs at Walt and jokes about him bringing a bag of meth to disparage him for stealing meth.

At this point, Walt reveals that the bag he brought doesn’t contain meth; it’s full of fulminated mercury. He throws a chunk of it at the floor, causing an explosion that blows out the windows and knocks everyone off their feet. Tuco relents when Walt threatens to drop the whole bag. As Walt heads back to his car, he experiences a rush that he’ll be chasing for the rest of the series.

When He Watched Jane Die

Walt watches Jane die in Breaking Bad

One of the darkest moments in Breaking Bad is when Walt sneaks into Jesse’s house, sees Jane dying of a heroin overdose, and allows it to happen. Walter White, the husband and father, wouldn’t let Jane die. There’s a moment where he considers saving her and wonders how he would feel if his newborn daughter Holly was in the same situation.

But the Heisenberg mindset takes over and reminds him that Jane’s influence over Jesse is having a negative effect on their drug business, and stops him from intervening.

When He Gave Skyler The “I Am The One Who Knocks” Speech

Walt's 'I am the one who knocks' speech in Breaking Bad

When Breaking Bad fans discuss the turning points that led to Walt leaving behind his moral compass and embracing the Heisenberg persona he created for himself, most of them will point to the iconic “I am the one who knocks” monologue.

In response to Skyler’s fear that he’s in danger, Walt erupts into a furious tirade in which he insists, “I am the danger!” He tells her he’s not the kind of person who opens his door and gets shot; he’s the kind of person who knocks on the door of somebody who’s about to get shot.

When He Laughed Maniacally In The Crawl Space

Walt laughs in the crawl space in Breaking Bad

After his former employer Gus Fring threatened to murder his wife and children, Walt raced to Saul’s office and demanded the services of “disappearer” Ed Galbraith. Saul told him it would cost half a million dollars, so Walt headed home to dig his hard-earned drug money out of the crawl space. But when he got down there, he found that most of the money was missing and Skyler confessed that she gave it to Ted Beneke to pay off the IRS.

When Walt realized he wasn’t in control of the situation, with Gus threatening his family and Hank catching up to him and his wife giving his fortunes to her lover, all he could do was laugh. The unnerving laughter at the end of “Crawl Space” is the clearest display of Walt’s hysterical instability in full-blown Heisenberg mode.

When He Killed Gus Fring

Walt speaks on the phone in Breaking Bad

Walt’s rivalry with Gus proved that his meth manufacturing career had nothing to do with providing for his family. It was all about being the best at something, and being in charge. After blowing up a nursing home to kill Gus, Walt had just two words to say: “I won.”

Mike summed it up perfectly a few episodes later in his final confrontation with Walt: “We had a good thing, you stupid son of a b***h! We had Fring. We had a lab. We had everything we needed, and it all ran like clockwork. You could’ve shut your mouth, cooked, and made as much money as you ever needed. It was perfect. But no, you just had to blow it up. You and your pride and your ego!”

When He Forced Declan To Say His Name

Walt forces Declan to say his name in Breaking Bad

In Gus’ absence, Walt, Jesse, and Mike went into business for themselves. Whereas Jesse and Mike wanted to secure a one-off fortune and make a clean break, Walt wanted to build a sustainable empire. Their Phoenix-based competitor Declan initially offers to buy the trio’s stolen methylamine for $15 million, which would give all three of them enough money to retire happily, in exchange for getting Walt’s blue meth off the market.

But that deal wouldn’t allow Walt to run an empire, so he refuses and instead offers to produce his superior meth for Declan’s distributors. Declan initially refuses to accept Walt’s proposal, but reluctantly accepts when Walt forces him to “say my name” and he realizes Walt is the infamous Heisenberg.

When He Had All Of Mike’s Men Killed In Prison

Walt talks to Jack in Breaking Bad

Hank’s last chance to piece together the mystery of Gus Fring’s drug operation was to speak to Mike’s surviving henchmen and their lawyer, who were all behind bars. But before he could interview the witnesses, Walt used his connections to Jack’s neo-Nazi gang to have them all whacked in prison in the space of two minutes.

Orchestrating this string of killings and calmly awaiting the call that confirms it’s done is the moment that Mr. Chips had truly transformed into Scarface.

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