First of all, here are two pretty cool graphics about the show:
There are a bunch of recurring things in BB, such as Walt's cancer, the ricin vial, Walt knocking himself unconscious in the bathroom, Jesse and Heisenberg applying makeup to their faces to hide bruises, the street dealers (under Gus) and Todd (under Heisenberg) killing a child, etc. I just watched the preview trailer for next Sunday's episode, "Rabid Dog". It ends with the shadowy figure of Heisenberg (not Walt, since Walt died laughing in the crawl space in one of the final episodes of season 4) sitting poolside in the dark, with Jesse's voiceover calling him "the devil." A huge recurring thing is that nothing good can come out of Walt/Heisenberg sitting poolside. He was poolside when calling Hank to go on the DEA raid in the pilot episode, when watching Wayfarer 515 fall out of the sky, when deciding to poison Brock and frame Gus, when Skyler attempted to drown herself, and when Hank discovered Walt was Heisenberg.
All I can say is, hold on to your hats.