Bobby and his team respond to an emergency at a children's birthday party; the crew jumps into action after one of their own is involved in a devastating accident; Athena tries to cope with a tragedy that hits way too close to home.
Bobby and the team race to help the survivors of a deadly plane crash; Athena deals with chaos at the airport; Bobby confronts his past demons; Athena is out for revenge against teen bullies; Abby delivers an important message from a 9-1-1 caller.
Chastain picks up the pieces after the fallout with the corrupt medical device company Quovadis; Conrad and Alec team up to help a young gymnast experiencing mysterious symptoms; Bell rushes to Kit's aid.
J.J. is shaken after investigating the case of two abducted children, and tells her husband about the events.