All the Tuco scenes are just recaps, so the first few chapters remain relatively the same as the orginal..
FLASHBACK:
Back when they first started, Jesse tries to sell Walt's new product to Jesse's business partner, Krazy-8, but Krazy-8's cousin Emilio suspects Jesse of ratting him out to the DEA. Unknown to Emilio, it was in fact Krazy-8 himself who snitched on his own cousin.
Upon meeting him, Emilio recognizes Walt (who still had hair back than) from accompanying Hank during a ride along, and believes Walt to be a uncover cop so both Emilio and Krazy-8 draw there guns and plan to kill Walt and Jesse.
Walt, who in a last ditch effort to save himself, offered to teach them his meth formula. Emilio and Krazy-8 agree and both follow Walt into the RV Walt uses for cooking. While mixing chemicals, Walt intentionally creates a small explosion that produces phosphine gas, choking and incapacitating both Emilio and Krazy-8 while Walt himself had managed to escape unharmed. Emilio is killed but Krazy-8 later reveals to have survived, though barely.
The still alive Krazy-8 is tied to Jesse's basement. Walt, still being relatively innocent back than, desperately tried to find any reason let 8 go free. However while retrieving the key to the bike lock, he notices a shard of plate missing from when he fell unconscious during one of his lung cancer fits. Realizing that Krazy-8 stole the shard and has manipulated him in to freeing him and will kill him immediately once freed, Walt realizes he has no choice but to kill him.
Walt, playing innocent, goes back to the basement and Krazy-8 assures him "You're doing the right thing".
"The moment I do.. Are you going to stick me with that broken piece of plate?" Walt nervously asked, a tear coming down his face.
Realizing he has been caught, Krazy-8 attacks but Walt pulls back on the bike lock, choking Krazy-8 against the pole as Krazy-8 desperately swings the plate shard back trying to hit Walt. Walt dodged the swings until he puts his leg against the pole to get more leverage and Krazy-8 finally dies, though he manages to badly cut Walt's leg.
Poor Walt immediately falls into tears over this, he never killed anyone before.. Nor has Jesse.
Walter, now bald, and his former student now turned business partner, Jesse Pinkman, meet Tuco and his men in a empty junkyard, where Walt delivers two pounds of his clear glass meth, as promised.
Walter is seen wearing a top hat and black suit, and he and Jesse both have sunglasses on.
Walt explains to Tuco that due to a "production problem," they will have to delay the delivery of the rest of the first batch. Tuco is annoyed, and as an apology, Walt offers to extend his offer to four pounds, much to Jesse's shock and disagreement.
Tuco agrees but delivers a stern warning: "Talk is talk. But owing me money, that's bad."
Back home, Jesse criticizes at "Mr White", for his impulsive promise, saying there's no way they are gonna make 4 pounds of meth. Walt says they'll produce their own ingredients, but when he hands Jesse a list of chemicals and equipment to buy, Jesse tries to back out, arguing "I can't pronunce half this shit!".
Walt encourages him to believe in himself, and Jesse reluctantly agrees to take on the endeavor.
Jesse does his best to get the stuff, but only comes back with half of them, saying he did what he could but couldn't get them all. Walt realizes they are missing a key chemical, methylamine. After some brainstorming Walt eventually decides to steal it themselves.
That night the two sneak into a labatory. Walt pulls out a green and red ski mask which Jesse criticizes, saying they would look silly in those.
"Was all they had." an annoyed Walt replied.
"Than you try another store..."
"Enough, lets just do this." Walter answered, Jesse sighs and follows his lead, taking the red one.
After locking a guard inside a portable toilet, Walt and Jesse break into a warehouse, carrying a large barrel of methylamine off with them. Managing to get away with it, least this time. And they are smart enough to not be pushing their luck with a second attempt.
The barrel's meterial ends up turning the meth blue instead of the usual cystal white, though this later becomes Walt's trademark, blue meth.
A few days later they meet back with Tuco, giving him the 4 pounds as promised.
"What is this shit? It's blue."
"We used a different chemical process, but it's every bit as pure." Walt explained, trying to sound as professional as he can.
"It may be blue, but it's the bomb." Jesse added, doing the same.
Tuco snorts some of it right it into his nose from a knife tip, something he has a habit of doing quite regularly.
"Haha, blue, yellow, pink, whatever just more of that! That's good shit!" Tuco said excitedly, handing them a bag of money. "We are gonna make a lot of money together!" he added. Walt doesn't reply, just a silent node before turning to leave.
"Just remember who your working for." Tuco's goon, No-Doz, warned them. Walt turns back, a bit surprised.
"What you say?" Tuco asked, clearly angry.
"Just that.. They should know they're working for you." No-Doz said nervously.
"Like they don't already know that.. Are you saying that's they're stupid?!" Tuco asked angrily.
"No.." No-Doz said nervously.
"So your not saying that'll stupid.. So I'm confused here, you saying that I'M stupid?!"
"Tuco, I'm just saying..." No-Doz insisted.
"NO YOUR SPEAKING FOR ME! LIKE I DON'T HAVE THE GOD DAMN SENSE! TO SPEAK FOR MYSELF!" Tuco suddenly screamed loudly. "That it? That what your doing?" he asked, suddenly in half whisper, getting in the man's face, mad dogging him.
"Tuco let's.. Let's just relax alright?" Walt insisted, trying to calm the situration peacefully. Tuco pauses than suddenly laughs this off.
"Hesinberg says relax.. I'm relaxed, I'm..."
Without warning Tuco suddenly explodes into violence, punching No-Doz square in the face and knocking him down. Tuco leaps onto him, violently beating on No-Doz, til his face is left a bloody pulp. In between this, we see Walt growing more and more horrified, as if finally realizing the danger he put himself in.
"HA! DAMN MAN, LOOK AT THAT, LOOK!" Tuco screamed, excitedly showing off his bloody fist to the jawdropped Walter and Jesse.
"Okay Hesinberg.. Next Week." Tuco said with another laugh, and he leaves. His other goon carrying No-Doz to Tuco's car with them.
Walt and Jesse remain silent as they walk back to Jesse's car.