3. Season 10
Continuing the story from the end of Season 9, the Season 10 opener titled “Mayday” sees the men and women of Firehouse 51 rescuing the victims of a boat that capsized on Lake Michigan, and Cruz nearly drowns during the incident. Though he survives, Cruz is left with PTSD, which becomes an ongoing story for the season as he struggles to come to grips with his near-death experience. Meanwhile, Griffin Darden — the son of the late Andy Darden — arrives back at the firehouse, and Casey takes it upon himself to help him after discovering that he and his brother are living alone in the Pacific Northwest. But helping them may also mean leaving Chicago for good.
Boden is facing career-altering choices too, as he accepts a promotion to become the new Deputy District Chief, while the arrival of new interim truck lieutenant Jason Pelham creates problems for just about everyone. But when his position at the firehouse is threatened, the squad bands together to try to help him. Interpersonal problems crop up between Violet and Gallo after she spends the night with another man, while Kidd fears that Severide may have feelings for another woman.
Season 10 includes the show’s milestone 200th episode — fittingly titled “Two Hundred” — which sees an emotional farewell and the welcoming of a new baby. The season ends on a high with a wedding, in “The Magnificent City of Chicago,” which also sees Casey’s triumphant return.
2. Season 2
Going from “pretty good” to one of the best prime-time dramas on network television, the second year of “Chicago Fire” is nearly the best season the show produced and a marked improvement on the first season. It does it by introducing new ongoing dramas, and continuing old ones, beginning with firefighter Casey, who finds himself growing closer to the Darden family after finally making amends with Heather, the wife of his lost comrade. But when she runs into trouble following a devastating car accident, she may face prison time, leaving Casey to step in to help the family.
At the same time, Severide believes he’s being hunted by a deadly arsonist and takes it upon himself to track down the culprit. To his surprise, he comes to believe it could be a former firefighter he once worked with at another firehouse. But the biggest problems facing Firehouse 51 aren’t dangerous blazes this season, but city budget cuts that could get them closed down, as Chief Boden is pressured to resign his position. And when it’s discovered that the squad may have a mole in their midst, all hell breaks loose.
The highlight of the season is “A Dark Day,” another crossover with “Chicago P.D.” that is inspired by the 2013 Boston Bombing that revolved around a bomb attack at a charity run that sends the entire city into a panic. The season closes out on a brutal, nail-biting cliffhanger that opens with a fire at a boarding school.
1. Season 6
“Chicago Fire” seemed to peak with Season 2, but it somehow managed to top it four years later in Season 6, which ranks as the best-ever season for the show to date. It starts with a bang, with the jaw-dropping conclusion to the previous season’s cliffhanger which had the squad inside a flaming warehouse while Mouch was suffering cardiac arrest. Flash forward a couple of months, and Casey is promoted and decorated for his bravery, while a fire at a local school where Boden’s wife works is found to be no accident after all.
As Casey is adjusting to his new role as fire captain, a new chief clashes with the crew when Boden works on a new assignment, which leads to a series of cascading problems at Firehouse 51. In a crossover episode with “Chicago P.D.,” Detective Voigt arrives looking for help, asking Dawson and Brett to go undercover to assist in a case involving a deadly serial bomber. “The Chance to Forgive” is the season’s best, with a story that puts several relationships to the forefront, while a house fire leads to an unimaginably deadly situation.
Topping off the best year of “Chicago Fire” is the season finale “The Grand Gesture.” In the closing episode, Boden continues his run for city commissioner but faces mounting questions when details of his troubled personal life go public. Well-written and tightly paced with plenty of personal drama and epic action, Season 6 is as good as the show gets.
