Melvin Abston

When a teenage sex worker disappears, Rollins and Velasco find a key clue in a pile of neglected missing persons reports.

A young woman wakes up in the hospital with no memory of her assault, and Carisi's (Peter Scanavino) investigation stalls when she disappears.

A gunman open fires at a local college, sending mass casualties to the hospital; Arizona's return is not warmly welcomed.

The hospital is hit with an unprecedented crisis; Meredith and Cristina's surgical skills are put to the test.

After a former officer waits on Frank at a restaurant, he feels guilty about the circumstances surrounding why she was fired, and he tries to reinstate her. Also, Danny and Baez investigate the murder of a star college basketball player linked to sports betting, Erin seeks justice in an apparent DUI, and Jamie and Eddie pick a wedding venue.

When Sabrina is arrested after attending an Occupy Natesville protest, one of the jail attendants (Katy Perry) commits to making her imprisonment as awful as possible; Virginia helps the mayor avoid a scandal.