Andy becomes painfully suspicious of the circumstances surrounding her mother’s death and goes to her aunt looking for answers. Meanwhile, the members of the crew work to evacuate a doctor from Pac-North hospital and find themselves in a life-threatening situation; and Sullivan undergoes surgery for his chronic leg pain.

When Theo and Vic hit a relationship milestone, Vic is forced to reckon with her feelings about commitment. Andy takes refuge at Dean’s home and helps care for Pruitt, while Dean considers a new potential career opportunity. Meanwhile, an explosion rips apart a neighborhood and changes the lives of our firefighters forever. The crossover continues on Grey's Anatomy S18E05: Bottle Up and Explode! (II)

When a wildfire threatens Seattle, the crew must jump into action to save their city. Meanwhile, as the station undergoes changes, Andy contemplates the future.

As Ben readies the new Physician Response Team truck for the field, his suspicions about Sullivan and the missing Fentanyl continue to grow. Meanwhile, Jack and Rigo try to look past their differences when they are forced to work together and fight a mysterious gas station fire; Dean and JJ try to work through their differing parenting styles; and Travis meets someone new.

While at a lunch seeking Pruitt’s blessing for their relationship, Andy and Sullivan jump into action when ICE attempts to raid the restaurant. Meanwhile, Travis gets roped into an awkward lunch with Chief Dixon, Emmett and Emmett’s girlfriend; and Ben invites Grey-Sloan Memorial surgeons Owen Hunt, Teddy Altman and Jackson Avery to get a sneak peek of the new PRT vehicle.

The Station 19 crew battles a storage facility fire with growing complications, and Dr. Jackson Avery pops over from Grey Sloan and ends up collaborating with old pal Ben Warren.

As Station 19 continues to battle an existential wildfire, the team grapples with the possibility of a future that will be changed forever.

Andy deals with the aftermath of a trauma.

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.

The members of Station 19 pack their gear and head to Los Angeles, California, to help battle a deadly wildfire raging out of control. While the team works to evacuate residents, they meet Terry, and Ben makes a split-second decision that changes both of their lives.

It’s the most wonderful time of the year and the firefighters have their hands full responding to a number of crises throughout Seattle. Putting aside their differences and personal drama, they come together to try and achieve a Christmas miracle.

The Station 19 crew trade in their turnouts for tuxes and gowns as they attend the Firefighters Ball, but when disaster strikes, they jump into action to save the day.

Station 19 and Station 23 each attempt to celebrate Thanksgiving following the fallout from the neighborhood explosion. The firefighters come together to cook, toast to loved ones they have lost, and celebrate the families they have become.

Maya addresses some unresolved family issues, and the crew takes matters into their own hands when faced with a life-or-death moment on scene. Meanwhile, Andy and Sullivan’s marriage is put to the test.

Dixon threatens Natasha in the aftermath of his poor judgement. Meanwhile, Jack is met with disappointment on his first day back. Diane visits Maya, and the team responds to a fire in Theo's old neighborhood.

The team responds to a tragic freeway pileup. Andy helps Natasha face the fallout of a recent decision just as Ben deals with the fallout of his own.

It’s election day at Station 19, with all eyes on the mayoral race. Andy, Theo and Sullivan vie to be named captain, and Vic forges an unexpected bond after going rogue.

The Station 19 team faces a grueling 24-hour shift that threatens to split them apart. Andy must make an impossible decision, and Maya and Carina navigate new parenthood.

The new Seattle fire chief is introduced to Station 19 and leaves the crew skeptical after his visit. Later, the firefighters are called to a department store fire caused by exploding fireworks, which triggers painful memories from Ben’s past and inspires him to pursue a new endeavor. Maya advocates for herself and her career, while Jack becomes more intertwined with an acquaintance; and Andy and Ryan have a heart-to-heart.

Ben and Jack mollify a group of homeless foster and biological siblings so they can help save a life, triggering memories from Jack’s past. Meanwhile, Maya pushes the team too hard and struggles to bring them together; and Pruitt threatens to take drastic action when refused a request.

When a blizzard hits Seattle, Travis must take a difficult call and members of the crew are forced to face their truths. Meanwhile, Ben has rising suspicions about a colleague.

When an Army veteran threatens to blow up a pawn shop, Sullivan reflects on his time as a Marine to deescalate the situation. Meanwhile, Vic and Dean try to reason with a man battling Alzheimer’s disease; and Pruitt takes a stand to honor fallen firefighters.

Vic rallies the crew to pose for a calendar photo shoot that will support a good cause. Meanwhile, Emmett comes clean to Ben and Sullivan, and shows Andy a softer side.

Andy returns to work while she and Jack fight to save people trapped in a collapsing bowling alley. Meanwhile, Ben confronts Sullivan about his drug problem; and Maya’s mother, Katherine, pays Maya a visit.

Ben, Jackson and Emmett are put in a precarious and dangerous position with a potential victim. Andy’s search for more background on her family opens her eyes, and Vic and Travis are caught in the middle of a corruption scheme.