Better Call Saul, Season 2

[Nacho is discussing his plan to have Mike kill Tuco]

Nacho:
You got a better plan? Go on, tell me. I'm all ears.

Mike:
You sure about this? Killing your partner, heh... that's a bell you don't unring.

[Nacho pauses, then pulls back his shirt to reveal something lodged in his shoulder]

Nacho:
You see this? You know how I got this? Back in '96, '97, Tuco and I were working with these bikers out of Riverside County. They were selling this peanut-butter crank; real shit, y'know, but cheap, we could sell it as fast as we got it. Anyway... Tuco develops a taste for it, and crank does not bring out the best in people - made Tuco erratic. Our connect was a guy called Dog Paulson. One day, Tuco's settling up with Dog. He decides to put on his lie detector. Dog's like, "What the hell," you know; Tuco just keeps staring at him, then he goes real quiet. "You think I'm an idiot, Dog?" He thinks Dog is supplying his competitor, trying to cut Tuco out. Dog, he denies it, "no way, not me." Tuco doesn't even raise his voice, but suddenly he's got a sawed-off and... right in Dog's face. I was behind him. Sickest thing I ever saw to this day, and this? [pulls back his shirt again] A piece of Dog's skull under the skin, a little piece of him. I tried digging it out, but it's in there pretty good. Y'know, not the kind of thing you go to the doctor's for. The thing about it was... Tuco really liked Dog. Kinda felt bad about it afterwards, but when he's using: [popping sound] Loco, crazy. There's no other way to put it. And he's using again: Crystal, much bigger kick. [shrugs] So... it's like you said. If Tuco finds out about my, y'know, independent ventures... it's gonna be Dog all over again. It's him or me.