Internal affairs takes a special interest in Detective Green after a gambler is found dead by his bullet and the investigation turns up a part of his past he's taken pains to conceal.
This is Jesse L. Martin's final episode and based on both the description and the commercial I saw last night during Special Victims Unit, it's going to be big.
This will also be Antony Anderson's first appearance as Detective Kevin Bernard, who is a different character from the one he played on Special Victims Unit a couple of years back.