[cosmo20002]

Originally Posted by Brainiac

We shouldn't be using spoiler tags, since these AREN'T spoilers. A spoiler is information that hasn't been aired. Anyone who hasn't seen the episode but reads these threads anyway after the episode has aired is doing so at his own risk. But, I'll play along:

Spoiler!

My thoughts EXACTLY! Brock was poisoned with the Lily of the Valley plant that we saw in Walt's back yard, and Jesse knew that it wasn't the Ricin that poisoned Brock (even though at first he thought it was the Ricin).

I figured that at some point this season Jesse would have to figure out that Walt either (1) poisoned Brock, or (2) allowed Jesse's landlord/girlfriend to die while choking on her own vomit when he could have easily saved her. They had to turn Jesse completely against Walt SOMEHOW, so that Jesse can eventually take Walt down.

OK, so I'm not off here. I think a key is that the DOCTORS told him it was Lilly of the Valley. It wasn't just Walt saying it. He might be suspicious or confused or whatever about the ricin, but this conclusion just doesn't really make complete sense.