When Jesse found the cigarettes and cancelled his trip to Alaska, I was confused. I found it hard to remember some of the finer points of Breaking Bad.

After doing some refreshing, here is the story behind the pack of cigarettes and the ricin:

  • Walt makes a ricin cigarette to poison Gus.
  • Jesse won’t poison Gus.
  • Walt has Huell (Saul’s henchman) pickpocket Jesse and take the cigarette.
  • Walt secretly poisons Brock.
  • Jesse blames Walt for the poisoning.
  • Walt convinces him one of Gus’s men stole Jesse’s cigarette and poisoned Brock so that Jesse would blame and kill Walt.
  • Jesse turns on Gus (Walt’s goal).
  • Jesse finds out Brock was not poisoned by ricin; he was poisoned by Lily of the Valley (LotV).
  • Walt used Lily of the Valley instead of ricin to poison Brock because he did not want to kill Brock or be linked (via ricin).
  • Jesse believes Brock must have accidentally ingested LotV; kids sometimes eat it.
  • Jesse now thinks he lost the cigarette since it wasn’t using in the poisoning.
  • Walt makes a fake cigarette and helps Jesse to find and get rid of it (to ease Jesse’s mind).
  • Walt has stored the ricin behind his electrical outlet switchplate for later use (he gets it from his ruined house at the start of season 5)
 Later, when Jesse is about to leave for Alaska:
  • Jesse looks for his weed and finds the pack of cigs with one cig missing.
  • Jesse realizes his weed was pickpocketed by Saul’s man Huell.
  • Jesse realizes the ricin was pickpocketed by Saul’s man Huell.
  • Jesse makes these realizations because he felt all along, despite evidence to the contrary, that Walt was behind Brock’s poisoning.
  • Jesse knows for sure that he has been manipulated by Walt to turn on Gus when Saul confirms that Walt had the cigarette lifted.

Hope that makes sense! Jesse did find the fake ricin cigarette and the doctor told him the poisoning was from LotV so there was no logical reason for him to suspect Walt. The plot hinges on the idea that Jesse never trusts Walt and thinks he’s capable of insidious plots. He admits as much to Hank after he tapes his confession. Honestly, I think the writers were just desperate to set up a confrontation between Walt and Jesse. It would have made more sense if Jesse turned against Walt over Mike’s death and the subsequent cover-up.

BONUS: Apparently show creator Vince Gilligan revealed in a Comic-Con panel some plot details that were not shown on screen. Walt went to Brock’s school and injected the LotV into his juice box. It’s not really necessary to know that detail; the show never tried to hide that Walt poisoned Brock. They made it pretty obvious throughout the plot arc and of course the reveal of the LotV plant in Walt’s yard was about as subtle as a sledgehammer.