Well-connected Special Agent Emily Prentiss joins the team, as they take on two serial killers, who seem to be in competition with each other.
In the aftermath of a deadly plane crash, Bobby and team race to help the survivors, while Athena deals with panic and chaos at the airport.
Intelligence investigate a bank robbery which leads them to a teenage gang run by an older criminal. Another detective from the robbery-homicide division tries to take over the investigation.
Chastain picks up the pieces after the fall out with the corrupt medical device company QuoVadis, leaving Marshall ready to charter new territory.
When the hospital has a severe blood shortage, Conrad must try every avenue to save a patient's life. Mina and Devon work with a new anaesthesiologist who is not what she seems and Nic receives devastating news.