n-methyl-1-phenyl-propan-2-amine, a.k.a. C10H15N, a.k.a. METH. Not just any meth - blue, super-pure Heisenberg meth. (That's a TV show lie, by the way...). In the end, Walter's evil plans include murder, hoards of cash, lying, cheating and stealing. Instead of 'muwah haa haa haa' or 'you just don't know the powah of the dark side', now we have, "Let's Cook!" and "Say my name."