10. Shades of Gray

Complete story — includes the ending

When a white bus driver runs into a pregnant woman in a black neighborhood, a riot breaks out that leaves both the driver and a West Indian passenger dead. The detectives question the witnesses and themselves about the effect that race may have played in this violence, and are surprised at the answers they find. Lewis' discovery of a police uniform button near the passenger's body leads the squad to an officer who had been questioned in the shooting death of a black man five years earlier. (See the season two episodes " See No Evil " and " Black and Blue ".) As Lewis and Sheppard track down a witness, Sheppard suffers a brutal beating and loses her gun; Lewis is shot at and nearly killed as well. The gun is returned after an angry Lewis speaks to a packed West Indian dance club, and the officer and three other suspects are arrested in connection with the two deaths.