Anthony Ferraris

Kidd and Severide's honeymoon is interrupted by a dangerous person from their past; Kidd's former academy classmate joins Firehouse 51; Brett and Violet reflect on their relationships.

Boden pushes his team to pull it together in the aftermath of the explosion; Casey works to track down a missing Severide; Newhouse brings news about one of Mills' relatives; Herrmann and Otis come up with new goals.

Severide wants to implicate the serial arsonist; Dawson and Shay face the unexpected on a routine call; suspicions indicate Clarke is the mole; Mouch campaigns for union president.

Firehouse 51 responds to an unusual call from another firehouse; the addition of a new firefighter (Miranda Rae Mayo) has repercussions; Casey realizes that certain voters have personal agendas for wanting him elected.

Detective Holloway testifies in court as part of an undercover operation, leaving Severide to watch her young son; a fire at an art gallery with a victim trapped inside leads Cruz to make a rash decision.

When new evidence appears in the internal affairs investigation that will clear Chief Boden, a twist puts him right back in the thick of it; Brett and Chili try to save a stabbing victim from bleeding to death.