As he and Jesse clean up the liquefied remains of Emilio, Walt's thoughts go back to his time working as a scientist. He and a female assistant count the percentages of elements in the human body, but after taking into account every known element, still come up less than one percent short of an entire body, with Walt musing that there must be more to a human than their chemical makeup...
As Skyler tries (and fails) to subtly get Marie's insight on Walt's apparent marijuana use and accidentally implies that Junior smokes weed, Walt goes to check on Krazy-8. To his horror, Krazy-8 not only knows his name, but knows of his family, apparently from Jesse. Walt storms in on Jesse as he tries to take the edge off in the restroom with some meth, and the two get into a scuffle over Jesse's baggy of meth before Jesse leaves, calling Walt out on not honoring his end of the bargain they struck by flipping a coin and offing Krazy-8.
Marie tells Hank about Junior's apparent weed use as she indulges her kleptomania by stealing expensive shoes, and Hank tries to scare Junior straight by taking him to the Crystal Palace, a shady motel, and introducing him to Wendy, a meth-abusing prostitute. The lessons Hank try to impart on Junior don't really reach through to him (since he doesn't light up) as Wendy returns to her motel room, where Jesse is waiting to solicit her services...
Back at Jesse's house, Walt struggles with whether to kill Krazy-8, jotting down a list of reasons to either spare him or kill him. He comes up with several reasons to let him go, and only one to kill him: "He'll kill your entire family if you let him go." With the day growing late, Walt calls Skyler and tells her that he'll be working overtime at the car wash. Skyler, however, has found out that he quit working at the car wash, and dismissively tells him to do as he please.
Walt prepares a sandwich for Krazy-8, but when he goes to deliver it to him, suffers a coughing fit and loses consciousness. When he comes to, he reveals to Krazy-8 that he has lung cancer. When he returns with a second sandwich, Krazy-8 advises him that it would be easier in the long run just to kill him. Walt, still undecided as to what to do with him, implores him; "Sell me."
Walt and Krazy-8 bond over the latter's musical aspirations, as well as his father being the owner of a furniture store with a catchy commercial jingle, the same furniture store where Walt bought the crib for his son. Krazy-8 learns that Walt hasn't told his family about his illness, and realizes Walt's reason for getting into the meth trade: to make money for his family, so that they could get by after he was gone.
As Walt returns upstairs to get the key to the bike lock confining Krazy-8 to a support column in the basement, however, something occurs to him. He digs out the pieces of the broken plate from when he passed out and tries to piece it together, only to find that one shard of the plate was missing! Krazy-8 had taken the shard, and was no doubt planning to kill him with it if given the chance.
When Walt returns to the basement, he prepares to unlock the bike lock, but before he does so, he asks Krazy-8 if he intends to kill him. Krazy-8 immediately tries to kill Walt, but Walt pulls on the bike lock and chokes Krazy-8 to death, apologizing all the while.
When Jesse returns the following morning, his basement is completely empty...
As Hank investigates Walt's original cook site, Walt is parked under an overpass, thinking back to his time at the lab, still pondering what was still missing in the chemical makeup of the human body. When his lab assistant ponders if maybe what they were missing was a soul, he dismisses the notion, stating "There's nothing but chemistry here."
Walt finally makes a decision. He returns home to Skyler, ready to confess to her his secret...
This episode provides examples of:
- Affably Evil: Krazy-8 treats Walt with a lot of politeness and is even willing to reminisce about his upbringing with his captor. It turns out that he's attempting to use his amiability as a ploy in order to get Walt to free him, and then exact revenge on him.
- Bottle Episode: The episode takes place mostly in Jesse's house.
- Buffy Speak: Marie complains about her ugly shoes, saying she only wears them for support because "[her] arches happen to be extremely archy".
- Chekhov's Gun: The broken dish. Krazy-8 takes a shard while Walt is unconscious to attack him.
- Chekhov's Gunman: Gretchen makes an unnamed appearance in a Flashback a full two episodes before she enters the story.
- Compound Title: With the previous episode. "The Cat's In The Bag...And The Bag's In The River".
- Ear Worm: In-Universe example: the jingle from Tampico's Furniture store.
- It's for a Book: Skyler claims she's asking Marie about weed for a "character in a short story she's writing". Marie is not fooled.
- Oh, Crap!: Walt when he realizes where the missing shard of the dish is.
- Police Are Useless: Averted with Hank and Gomez quickly determining what took place at the cook site.
- Reality Ensues: Continuing from episode 2, Walt and Jesse are forced to deal with realistic consequences of murdering two people and hiding the evidence.
- The Reveal: That plate that Walt broke when he fell in front of Krazy-8? There's a piece of it missing that Krazy-8 will use to kill Walter once free.
- Scare 'em Straight: Hank pulls this on Walter Jr. to discourage him from smoking pot. Hilarious because Walter Jr. is not using any illegal drugs and is very confused as to why Hank is suddenly making such a big issue of it, while Hank thinks Junior is just trying to play it cool and gets even more over the top to make his point.
- Sequel Hook: Walt's line to Skyler: "There's something I have to tell you."
- Sticky Fingers: Marie steals a pair of shoes from a shoe store with an annoying clerk.
- Wham Episode: Walt commits his second murder, strangling Krazy-8 in Jesse's basement.