Burgess stops a man with a trunk full of heroin at a sobriety checkpoint.
Voight and Antonio question the professor, but he claims he had no idea the drugs were in there.
Roman asks Platt for a letter of recommendation to become a field training officer. She wants to take him out on a field test.
Lindsay asks Voight to let Burgess partner with her for the day. They question the professor's wife and daughter.
Intelligence follows a lead and finds a house on fire and a burnt body. Brett tells them he was burnt alive. They also find the body of a 9 year old boy who had been shot.
Lindsay and Burgess talk to the burnt victim's girlfriend. She gives them a name. He kills himself.
They find out the professor has a secret apartment. They find letters from prisoners.
Mouse recommends Halstead for a security job at a marijuana clinic. He accepts the job.
Ames admits he's in love with one of the prisoners, Peter, he's been writing to, who is out.
Ames' daughter is kidnapped for ransom.
They get a name from Peter after threatening his brother. They rescue the girl.
Halstead starts his new security job.