Chicago Fire - Season?4 (premiered?October?13,?2015; concluded?May?17,?2016) follows the firefighters, rescue squad, and paramedics of Firehouse?51 as they tackle 23 high-stakes episodes filled with life-or-death emergencies and personal drama
Major storylines include:
- Severide's trial by fire: Facing potential demotion and taking on arson investigations, Kelly Severide fights to reclaim his standing
- Casey undercover: Matthew Casey embeds with Chicago PD to take down a human-trafficking ring, sparking turbulent consequences
- Dawson's shift & tragedy: Gabriela Dawson moves into the Office of Fire Investigations and endures pregnancy complications, while rescuing and fostering a young boy
- Herrmann's near-death: A stabbing lands Christopher Herrmann in critical condition, with his recovery spread across crossover episodes
- Political drama: Casey runs a city campaign for alderman, facing public pressure and ethical dilemmas
- Building under siege: In "Where the Collapse Started," Rescue Squad and Truck navigate a dangerous building collapse to save trapped individuals
