After agreeing to an ultimatum presented because of the cartel, Gus takes Mike and Jesse down with him to Mexico, the place they have Jesse train the cartel researchers (led by Benicio Fuentes) how you can cook the blue meth. Gus returns from Mexico and his partnership with Walt unravels, https://blue-crystal-math94468.bleepblogs.com/30069707/not-known-factual-statements-about-blue-crystal-math