[Shaun]

I read some theories on IMDb as to what happens in S5, but this is total fan speculation, I just liked the idea

Spoiler:

Since there's a massive timebomb between Jesse and Walt, what with Walt first letting his gf die and then 2nd poisoning his new gf's kid, Jesse could team up with Mike, who'll probably have had a personal connection to Gus since he got into a bar-fight with Walt over the idea of turning on him.

But how Jesse finds out about any of Walt's actions will be interesting. I suppose having Lily of the Valley in his back yard is a bit of a risk but then it's too common a plant to make him suspicious.