Tuco Salamanca was a prominent character in the first two seasons of Breaking Bad, but much of his backstory wasn't revealed until Better Call Saul. The character, played by Raymond Cruz, was introduced at the tail-end of Breaking Bad season 1, but the actor reprised his role for the prequel series. The nephew of Hector Salamanca acquired a number of enemies during his time working for the cartel.

Tuco first became involved with Walter White and Jesse Pinkman's operations after he was introduced by Skinny Pete. Jesse delivered a pound of meth but Tuco stole the drugs and refused to make a deal. Walter learned of the confrontation so he arrived at Tuco's hideout under the persona "Heisenberg." Tuco rejected Walt's request for more money so he threw a crystal, causing an explosion. Tuco was impressed by Walt so he agreed to be his new meth distributor. After a few deliveries, Walt and Jesse realized that Tuco was unhinged and extremely violent.

Related: Hector Salamanca’s Breaking Bad Backstory (Revealed In Better Call Saul)

In Breaking Bad season 2, Tuco kidnapped Walt and Jesse after the DEA raided his hideout. Tuco took them to a house in the desert where he lived with his disabled uncle, Hector. He was planning on taking Walt and Jesse south of the border, so they could cook meth in a Mexican superlab. While in the desert, Walt concocted a plan to poison Tuco with ricin. He planted the ricin in Tuco's burrito but Hector witnessed it and made sure his nephew didn't eat the food. Walt and Jesse get into a confrontation with Tuco shortly after, when Hank showed up. He had been tracking Jesse's car and searching for Walt, leading him to the desert. Tuco and Hank got into a wild shootout before the DEA agent shot the drug kingpin in the head. It was later revealed that the Salamanca family had strong ties to the Juárez Cartel, which would come into play in the prequel series.

Tuco threatens Jimmy in the desert

In Better Call Saul, Tuco's role in the cartel was explained to be larger than first thought. Hector was one of the highest-ranking members in the drug trade and he groomed Tuco to one day take his place. Tuco still had erratic behavior in the prequel series but he had better control over his emotions. He first encountered Jimmy McGill (aka Saul Goodman) after the lawyer set up a scam with a pair of skateboarders who targeted the wrong elderly woman. Instead, they scammed Tuco's grandmother, so he took Jimmy and the skateboarders out into the desert to kill them. Jimmy used his smooth-talking ways to talk Tuco out of the murders and it surprisingly worked.

Tuco's associate, Nacho Varga, became concerned about his partner's behavior so he turned to Mike Ehrmantraut for help. Nacho requested that Mike kill Tuco, but he came up with another plan. Mike started an altercation with Tuco in a public place, getting the man arrested for assault. Unfortunately, Mike was then visited by Hector, who wanted the charges on his nephew dropped. Hector viewed Tuco as his son and the Salamanca family was a loyal bunch. After threats against the Ehrmantraut family, Mike reluctantly agreed to get the charges lessened.

While in prison during Better Call Saul season 3, Tuco got his sentence prolonged after stabbing another inmate and assaulting a guard. He would stay in prison until the events of Breaking Bad. Over those years, Tuco's behavior and mental state gradually worsened. He became angrier and more violent by the time he got out of jail. Once he got hooked on meth, there was no turning back for Tuco. Walt's blue meth was so pure that Tuco couldn't resist the drug and he lost his mind.

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