My guess for tonight's Breaking Bad
I'm guessing Walt comes across some Blue, realizes Jessie is alive, and goes to either kill or save Jessie.
The cigarette is for Jack and Co (and maybe Jessie), luckily, Jessie has the Hazmat suit now that he's cooking (though so does Todd). Todd gets his comeuppance at the hands of Jessie in the aftermath, and then I don't know.
Even if Walt has come to save him (I hope so, would be good to see them as a team one last time), he still has to be furious about Jane.