When the team responds to an apartment fire, Captain Pruitt takes a hit, the future of the station's leadership is in jeopardy and firefighter Andy Herrera is forced to step up. Meanwhile, new recruit Ben Warren is trading in the scalpel for a fresh start as a firefighter, but it hasn't been easy and he has a hard time realizing that emergencies in the field are vastly different than those at Grey Sloan Memorial.
With the absence of Captain Pruitt, Andy and Jack try to navigate how to work together, and a car accident on a rural road puts both the victims and the crew's lives at risk.
Upon the arrival of Batallion Chief Frankel, Jack begins his first shift as co-captain and continues to butt heads with Andy on leadership styles. Captain Pruitt has a difficult time following doctor's orders and winds up back at the station to take on administrative duties. Meanwhile, the rest of the team at Station 19 responds to an attic fire at JJ's apartment building and a call to a pool house party.
As if being co-captains weren't hard enough, Andy and Jack find themselves in disagreement over spending decisions at the station. Meanwhile, the firefighters respond to a structure fire at a brand-new bed-and-breakfast; and Ryan calls Maya when he finds her brother in some trouble.
Miranda Bailey visits Ben at work, meeting his new co-workers for the first time. While most of the team responds to a motor vehicle accident involving an electrical danger, Andy and Maya are paired up to go on their first stakeout.
Andy, Jack and 18 other candidates take the captaincy drill test, gunning for one spot as captain of Station 19. Meanwhile, Travis is serving as acting captain while Andy and Jack are away for the day; and Ben confronts Vic about her fears.
Ryan tags along to a disaster drill training at Station 19 where he and Jack get competitive. Captain Pruitt's health weakens and Andy is sticking by his side. Meanwhile, both the firehouse crew and police department respond to a strip mall fire, forcing Jack and Ryan to work together.
Ripley interviews each member of the Station 19 crew to determine whether Andy or Jack should be given the role of captain. Meanwhile, a mom's day out on a party bus takes a turn for the worst; and Captain Pruitt continues his treatment.
In the final days before the Station 19 captaincy is announced, Pruitt warns Andy not to be disappointed with the outcome. Meanwhile, Ben gets upset with Pruitt for having told Bailey the dangers of firefighting; and the team gets trapped inside the garage of a burning house, putting several lives at risk.
Ben reaches a new milestone as a rookie and, as is tradition, receives something from the crew. Chief Ripley holds final interviews for the role of captain but is interrupted when the team is called to a massive skyscraper fire, causing several lives to hang in the balance.