As he surveys the RV, Walt gives Jesse a stern lecture on how they will conduct business from now on: Walt is to be the "silent partner" who handles the chemistry side of the operation while Jesse deals on the street. Walt further stresses that he wants "no more bloodshed." This scene is intercut with shots of a bald man calmly walking through a group of bikers on a street littered with smoldering debris. As we pan up and his face is revealed, the bald man is revealed to be Walt in a flashforward.
Walt receives treatment at the cancer clinic, convincing Skyler to leave him. Before departing, Skyler expresses concern that the check promised to them by Elliott has not been received. Walt falsely claims that he has deposited Elliott's check, but later asks the clinic's clerk not to deposit his own check until Monday.
The next day, Walt uses the example of fulminated mercury to teach his students how rapid chemical reactions can cause otherwise harmless substances to explode. Before he can finish his lesson, Walt abruptly leaves to vomit in the men's room, after which a school custodian named Hugo assists him. At a cancer support group, Skyler tells Walt she feels he doesn't want her around, and that she and Junior wonder where he disappears some afternoons. Walt says he needs to be alone sometimes, and that he goes on nature walks.
While cooking in the RV, Walt struggles to breathe and stumbles outside. Jesse assists Walt and quickly deduces that he has cancer, having had an aunt who also struggled with the disease. Jesse further realizes that the reason Walt has begun cooking meth is to financially provide for his family after he dies. When Walt can't continue cooking he tosses the respirator to Jesse, who heads into the RV to wrap up the cook.
Meanwhile, Gomez meets Hank in the parking lot of the Express Inn and hands him the gas mask that was discovered at Walt's original cook site. The crime lab report indicates the gas mask comes from Walt's high school.
At the Crystal Palace and around the city, Jesse sells the new meth batch to eager buyers. The next day, he gives Walt a pre-paid cell phone. Walt is dissatisfied with the $1,300 generated by the batch, but Jesse replies that it isn't easy selling meth "one 'teenth at a time." Wanting to move their product in bulk, Walt asks if Jesse knows any distributors. Jesse alludes to Krazy-8 being his distributor until Walt killed him. Jesse later tells Walt a "badass" named Tuco Salamanca has taken over Krazy-8's territory. Walt demands to meet Tuco, but Jesse insists that they stick with the less-risky approach of selling small quantities of meth.
Walt undergoes further treatment, which leads to more bouts of vomiting. Later, he gets a surprise visit from Hank, who presents him with the stolen gas mask that has now been linked to meth cooking. When Hank inventories the storage room in Walt's chemistry lab, he finds two gas masks missing along with some glassware. Jesse contacts Walt on his pre-paid phone, saying that Skinny Pete, who served time in jail with Tuco, is willing to introduce him. Hank warns Walt to keep a closer eye on his lab equipment, joking suggesting that people will suspect him of something drug-related.
Across town, Tuco tries some of Walt and Jesse's meth and, impressed, is eager to buy it. Jesse names his price as $35,000, but Tuco tells him he's running a "consignment operation" so Jesse will have to wait. When Jesse demands the money up front and attempts to flee with the meth, he is quickly caught by Tuco's henchmen. Tuco puts some money in a canvas bag, but ends up savagely beating Jesse.
At the high school, Hugo is arrested by the DEA. Over a poker game in Walt's living room, Hank explains that Hugo fit the profile for the lab thefts and that marijuana was found in his vehicle, the latter of which will cost him his job and land him in jail. Walt bets all his chips, causing Hank to fold. Hank looks shocked when Marie shows him Walt had a handful of nothing. As he takes a shower the next morning, Walt's hair falls out in clumps as a result of the chemotherapy. After calling Jesse, he finds out from Skinny Pete that Jesse has ended up in the hospital. There, Walt observes a sleeping Jesse wearing a neck brace and asks Skinny Pete to tell him about Tuco.
The next morning, upon finding more clumps of hair falling out, Walt shaves his head completely. Carrying a bag of what appears to be crystal meth, Walt talks his way into Tuco's hideout. Upon meeting Tuco, Walt identifies himself as "Heisenberg" and demands $50,000, equivalent to $35,000 for the stolen meth, plus $15,000 for Jesse's pain-and-suffering. Tuco and his gang laugh openly at Heisenberg's "brilliant plan", responding to Tuco's theft and assault on Jesse by bringing him even more meth to steal. Walt picks up a crystalline nugget from the bag and calmly informs Tuco, "this is not meth," and hurls it to the floor. The ensuing explosion blows out the windows in Tuco's office, sending debris falling onto the street below.
Ears ringing, coughing violently on plaster dust, Tuco's vision clears just in time to see Walt brandishing the packet of "meth" over his head, and hurriedly tells his men to put away their guns. He agrees to pay Walt the $50,000, and tells him that his meth sold faster than any other product he had ever seen. Walt agrees to sell his next batch to Tuco, provided that payment is made upfront and that Tuco agrees to accept at least two pounds. Before he leaves, Tuco asks what the "meth" in the bag actually is, and Walt reveals it is mercury fulminate.
Walt walks away from the ruined hideout carrying a bag full of cash. In his car, Walt clutches his newly earned wealth and vents his aggression, high on the rush of what he's just done. Regaining his composure, Walt drives away from the scene with police sirens in the distance.
- Uncensored on home video. Walt says, "Just grow some fucking balls!" and later on, Tuco proclaims, "Are you fucking nuts?"
- The episode title is a reference to a quote from the film Cool Hand Luke (1967). In the context of the episode itself, it's a reference to Walt's poker bluff, as well as his handful of a chemical explosive in the final scene with Tuco.
- In this episode, we see the birth of Walt's pseudonym, "Heisenberg." The name is a reference to Werner Heisenberg, a German theoretical physicist. Like Walt himself, Heisenberg was a school teacher who was diagnosed with cancer. Today, Heisenberg is mostly known for his "uncertainty principle."
- This is the first episode in which Walt is bald.
- The scene in which Walter is standing up in the bathroom stall after vomiting was actually taken from a scene where Walter is masturbating after a doctor's visit (the actual scene was never shown).
- In a 2018 interview on The Rich Eisen Show, Matt L. Jones (Badger) revealed that Badger was originally going to be the one to introduce Jesse to Tuco. However, the writers later re-wrote Skinny Pete into this role, as they felt a character like Badger would be highly unlikely to associate with someone like Tuco.
- Walt's appearance (Bald head with a mustache) continues until "ABQ".
- When Tuco's headquarters is blown up, if you listen closely, you'll notice that the sound effects guys dubbed in Howard Dean's infamous "Dean Scream" as a joke.
- The explosion in Tuco's hideout was replicated on a special episode of Mythbusters, which guest-starred Vince Gilligan and Aaron Paul. The Mythbusters team declared the myth "busted" because:
- Mercury fulminate appears as a coarse, yellowish powder; it does not resemble crystal methamphetamine closely enough that Tuco's men would mistake it for the latter;
- Although mercury fulminate is unstable and highly sensitive to friction, heat, electricity, or impact, a man cannot throw 50g onto a wooden floor with enough force to detonate it;
- 50g (the approximate weight of the crystal nugget Walt uses) would not produce enough explosive force to blow out the windows or walls;
- The explosion would certainly injure Walt more than anyone else in the room; and the larger amount (250g) that the team used not only blew out the windows and walls but also would have killed everyone in the room.
- Andrea Good as Laundry Worker
- At the beginning of the episode there is some time lapse B roll. One shows a church with traffic lights changing. This church shown is the First United Methodist Church on 3rd St & Lead Ave.
- Halfway into the episode there is a scene that shows Jesse selling meth at various places. These are some of the places shown in order. (They are all in a 4 blocks strip).
- Jesse & Skinny P visit Tucos headquarters, then Walt returns and blows it up. The building is now Java Joe's coffee shop (2016). 906 Park Ave SW, Albuquerque, NM.
- "Unknown Track #6" by Unknown Artist (heard briefly with Porter's music during the flash forward at the beginning of the episode as Walt walks away from the destruction at Tuco's lair)
- "It is Such a Good Night" by The Charlie Steinmann Orchestra and Choir (lyrics Paul Rothmann) (during the montage where Jesse sells meth all night)
- "Pa La Playa" by That Click Gang (playing outside Tuco's place before Jesse and Skinny Pete meet him)
- "Rompo" by Max One (while Jesse & Skinny Pete meet Tuco in his office)
- "Suntan Lotion" by Bearnie Leadon (during the poker game)
- "Follicles" by Dave Porter (as Walt examines his thinning hair and prepares to shave his head)
- "Los Pistoleros" by Jonaty Garcia (in the background when Walt goes to see Tuco)
- "Catch Yer Own Train" by The Silver Seas (as Walt drives away from Tuco's place)
- Walter: "Let's get something straight. This - the chemistry - is my realm. I am in charge of the cooking. Out there on the street, you deal with that. As far as our customers go, I don't want to know anything about them. I don't need to see them. I don't want to hear from them. I want no interaction with them whatsoever. This operation is you and me, and I'm the silent partner. You got any issues with that?"
- Jesse: "Whatever, man."
- Walter: "No matter what happens, no more bloodshed. No violence."
- ―Walter talking to Jesse about their operation.
- "This kicks like a mule with its balls wrapped in duct tape!"
- ―Tuco after tasting the drugs of Walter and Jesse.
- Tuco: "Let me get this straight. I steal your dope, I beat the piss out of your mule boy, and then you walk in here and you bring me more meth? That's a brilliant plan, ese."
- Gonzo: "Brilliant."
- Walter: "You got one part of that wrong. This is not meth."
- ―Tuco, Gonzo and Walter before Walter detonates Tuco's headquarters.
- "Chick’s got an ass like an onion... makes me wanna cry."
- ―Hank after meeting Principal Carmen Molina.