Brick (2005)

The lonely teenager Brendan finds his former girlfriend Emily dead in the entrance of a tunnel of sewage and recalls her phone call two days ago, when she said to him that she was in trouble. Brendan, who still loved Emily, met bad elements of his high-school trying to contact her, and when he succeeded, she told him that she was OK. He hides her body in the tunnel and decides to investigate the meaning and connection of four words, including "brick" and "pin", that Emily told him to find who killed her. Using the support of his nerd friend Brain, he successively meets the small time drug dealers Kara, Dode, Brad Bramish, Laura and Tugger, to reach the teenager powerful drug dealer The Pin. Slowly, Brendan unravels the motives why Emily was killed and plots a revenge.