Heroin is an opioid drug synthesized from morphine. Heroin is originally intended to be used as a pain-killer, but has become one of the most used illegal drugs due to its high addiction rate.
Miguel Esteana was arrested by Vic Mackey, who found eight bags of heroin on him. Mackey allegedly tortured Esteana with a pair of pliers, which prompted Esteana to file a complaint against him through his attorney, Jose Garcia.
When Armadillo Quintero returned to the US, he had his drug dealers distributing free heroin on schools. One of his dealers, Duardo, gave Felipe Gomez samples of free heroin and told him to distribute it at Truman East Middle School. One of the kids he dealt to, Enrique, was discovered and was taken to the principal's office. When the police came to check everything at school, they found out that hundreds of other kids had heroin on their lockers.
Some time later, a three-year old kid took one of the heroin samples from his brother's backpack. The kid ate it and died afterwards.
As the Strike Team tried to sneak out of a situation, Curtis Lemansky went into the house of a drug dealer and, after getting some information from him, he took a brick of tar heroin he had hidden. Emolia Melendez, who was the man's heroin cutter, witnessed this. Lem hid the brick on his glove box and didn't registered it as evidence.
Unknowingly, Internal Affairs verified Lem's car and found the brick of heroin and replaced it with a fake one. This was part of a confidential investigation against the Strike Team. The Strike Team later gave the brick to another drug dealer as payment, not knowing that the heroin was fake.
Emolia, who had witnessed Lem take the brick of heroin, later served as an IAD witness against the Strike Team.
With the charges of illegal drug possession for the brick of tar heroin, Jon Kavanaugh proceeded against Curtis Lemansky, with the intention of using him to get Vic Mackey. Lem was eventually arrested for drug possession.