Just after agreeing to an ultimatum specified through the cartel, Gus will take Mike and Jesse down with him to Mexico, wherever they've Jesse educate the cartel scientists (led by Benicio Fuentes) the best way to cook the blue meth. Gus returns from Mexico and his connection with Walt unravels, https://tysonioqqq.dbblog.net/2830358/the-best-side-of-blue-crystal-math