Alyssa, a 15-year-old schoolgirl is strangled and Russell, Jones and Medavoy investigate. Two of Alyssa's friends are brought in to help gather some background information, but one of them seems reticent to talk. Some essays that Alyssa wrote point to her having had sexual encounters. Her teacher can offer no assistance except a name cited in her last essay. The name mentioned leads the detectives to a suspect who is a registered sex-offender, but his alibi checks out. Later the reticent girl comes forward and reveals there was a relationship between Alyssa and her teacher. His story to the detectives reveals that he was trying to stop Alyssa's obsession with him, which he says started because of the encounters cited in her essays. Meanwhile, Sipowicz and Sorenson investigate the death of a man, where the only witness to the crime is a slightly crazy homeless guy with a TV and a microwave. Their investigation doesn't lead to a conclusive suspect, so they decide to keep their key witnes