"Breaking Bad" creator Vince Gilligan has spilled the beans on some unknown facts about the successful TV series.

As the final episode airs on Sept 29, take a look at what could have been.

"Breaking Bad" almost never happened. A show about a drug dealing science teacher wouldn't be easy by any count. Showtime, TNT, FX and HBO all passed on the chance to have one of TV's best dramas. (FX opted for the forgotten Courteney Cox tabloid drama 'Dirt.') AMC, flush with success from 'Mad Men,' took a gamble that paid off.

If you think the blue meth that Jesse and Walt cook up looks tasty, that's because it's technically edible. The crew uses crystallized sugar (or rock candy, as it's known to children) and blue food coloring to create the sweet, sweet meth that is the show revolves around.

And that's exactly right, as the 'Blue sky' will never really exist in real life. -- it's actually impossible to turn meth into the color of Papa Smurf. According to Dr. Donna Nelson, a professor of chemistry at the University of Oklahoma who also serves as the show's science consultant, "when you crystallize anything that's colorless, which methylamine crystals are, they usually come out with a yellow tinge because of impurities." She adds that Gilligan wanted Walt to have a signature meth, thus the blue color. Plus, it just looks cool. So relax already, science nerds.

Another character would have been the main villain. Hector "Tio" Salamanca and his trusty bell of doom were meant to play a bigger part on the series. Vince Gilligan revealed on the 'Breaking Bad' podcast that Tio was supposed to be the show's major villain from season 3 on. However, once the writers saw how Giancarlo Esposito's Gus Fring clicked with Walt and company, the decision was made to turn him into the show's main villain.