When a murder weapon from a case close to Athena in the early '90s resurfaces, flashbacks to 1989 show how Athena joined the LAPD and became the police officer she is today.

The members of the 118 rush to the site of a hit-and-run that leaves a familiar face in critical condition. Meanwhile, with Buck's help, Athena investigates the case of a missing woman last seen in a casino and Josh recalls an emergency in 2006 that led him to become a 9-1-1 operator.