For fans of 'Breaking Bad' that still remember Bryan Cranston as the geeky dad on 'Malcolm in the Middle' know that the actor transformed in at least one way for his foray into a different kind of series.

And though the actor came close to turning down the role of Walter White, he ultimately made a dramatic turn in the show. Fans were thrilled, and critics were impressed, too. But how did Bryan and his co-star Aaron Paul transform so convincingly into high-level criminals?

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As a fan on Quora recounted, not only did Bryan Cranston change his appearance to become Walter, but he and Aaron also underwent some unique training pre-filming. It was clearly worth the effort; both men made a killing on the AMC series.

As viewers recall, Cranston and Paul's on-screen characters turned to a life of crime in a bid to make money. They literally cooked up their own product to sell, which was the show's main premise.

On set, the two guys were actually going through the true motions of concocting the product, though. As that Quora fan highlighted, real DEA agents apparently walked Bryan and Aaron through the steps necessary to make the illegal substance in question.

Aaron Paul and Bryan Cranston in hazmat suits on the set of 'Breaking Bad'
via SciTechDaily

It was necessary to make the show seem more realistic, claimed the Quora user, since the show revolves around the pair's efforts to make a living off their home kitchen.

However, the real-life substance was actually cotton candy-flavored rock candy, says Quora, and everyone on set got to enjoy a bad habit once the crew started brewing the blue stuff. Aaron Paul even admitted to being "addicted" to the candy, though that's arguably preferable to hitting the hard stuff.

Plus, though the guys were schooled in how to cook up their on-screen rocks, the process depicted wasn't entirely accurate, notes Mental Floss. In fact, the chemistry professor who volunteered her expertise to ensure that the show got most of their science right admitted it. For one thing, the end result would be clear, not blue, said the source.

But in regard to everything else? The production team did the best they could to ensure accuracy with all their calculations, illicit substance ingredients, and more — all without actually giving viewers the strategies for going on to DIY at home.

Not that the show itself celebrates drug culture, says the chemist who proofed the script and calculated the ingredients for Bryan and Aaron. She noted that the show took a very realistic perspective of the negatives of such an enterprise, and the fact that the science was on point was just icing on the cake.

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