The routine arrest of a young man turns into a murder case when Amy finds him alone in the interrogation room beaten and drowned in his own blood.

Amy, the Ghost Squad's newest recruit, investigates a team of undercover cops who've been tracking a network of sex traffickers.

Sgt. Ralph Allen is an old-fashioned, no-nonsense copper. McKay suspects he is bringing the force into disrepute and needs to be removed.

Sally Marshall is the head of a serious-crime squad, but her clear-up rate is suspiciously high and officials suspect she might be cutting corners to get results.

Amy has three targets within the witness protection unit. One of them is desperate to prevent a murder witness from providing key testimony.

Sarah Houghton's profile suggests she's a good, dedicated cop, but the financial crimes unit reports irregularities in her bank account.