The First Responders rally together to search for a missing Maddie.

Athena, Maddie, Bobby and the 118 races to save lives after a massive tsunami hits the Santa Monica Pier and Buck fears the worst when Christopher goes missing.

A massive tsunami hits the Santa Monica Pier, placing Buck and Christopher's lives in danger .

In the aftermath of the shooting, Athena and the 118 are on high alert when a sniper is targeting members of the LAFD. Meanwhile, Maddie makes a life decision. Season finale

Maddie fears for herself and her co-workers when the call center is taken hostage.

The 118 deals with a situation where a stunt driver is placed in a precarious position, two mail bombs are detonated and a teenaged social influencer loses their mind; Eddie's family decides to visit; Buck confronts a deadly series of events.

The members of the 118 make calls to save a bridezilla at a disastrous wedding and to a mother trapped on her balcony. Meanwhile, Hen plays medical detective when her mother, Toni, falls ill. Also, Eddie and Christopher receive a visit from Carla, Athena uncovers a secret Bobby has been hiding that puts their marriage on the rocks and Maddie struggles with adjusting to motherhood.

Bobby meets Athena's parents for the first time and Maddie attempts to end her marriage for good, causing Doug to insinuate himself even deeper into Chimney's life. Meanwhile, a tanker carrying a tiger shark crashes on the freeway and a gas leak in a plastic surgeon's office happens mid-surgery.

The 118 rush to save lives in the aftermath of a massive train derailment.

The 118 races to the rescue when the 9-1-1 Call Center goes up in flames. Then, Bobby risks his life to save a trapped May, and Claudette, Buck and Eddie work together to help an injured electrician, and Chimney and his brother team up as firefighters for the first time.

When a murder weapon from a case close to Athena in the early '90s resurfaces, flashbacks to 1989 show how Athena joined the LAPD and became the police officer she is today.

Emergencies include a skating mishap at an ice show, an accident involving a self-driving car and a fulfillment warehouse robot going rogue. Meanwhile, Eddie's after-hours fight club gets out-of-control and Hen struggles in her relationship with Karen.

The 118 races to rescue a little girl in a runaway hot air balloon and help with a city power outage caused by a hijacked tree-trimmer truck; Athena's investigation into a serial rapist case puts her life in jeopardy.

The first responders continue to deal with the fallout of a massive earthquake and its deadly aftershocks. Athena tries to keep the peace as Bobby and team continue to rescue victims from a collapsing high-rise hotel, both under the rubble and high above the ground. Maddie 's first day on the job involves helping a pregnant couple deliver their baby safely.

When a massive earthquake rocks Los Angeles, the first responders rush to rescue victims from a crumbling high-rise hotel both under the rubble and high above the ground. Athena must deal with wreckage from a collapsed freeway overpass and Maddie is thrown into the fire as she faces her first crisis as a 911 dispatcher.

Athena and the 118 race to save lives after a drunk driver causes a deadly pile-up on the freeway. Meanwhile, Maddie goes into labor and Hen and Karen are devastated as they prepare their foster daughter, Nia, to be reunited with her birth mother.

The holidays are naughty and nice for the first responders, who must deal with a stampede at a toy store, a mistletoe stunt gone awry and neighbors competing in a Christmas-light showdown. Meanwhile, Bobby contemplates his future with Athena, Chimney and Buck attempt to lift Maddie's spirits and Eddie must decide if he wants to give his son what he really wants for Christmas - a visit with his mom.

Athena's only chance of surviving and saving everyone on the flight is to attempt to land the plane before it crashes and call on the 118 for help.

Eddie's journey to rescue a boy from a well turns into a mission to save himself from his past.

Accidents happen at a bowling alley and a home renovation; Athena pursues a car thief.

A series of freeway car accidents leads to a catastrophic overpass collapse that endangers the lives of civilians and members of the 118.

The 118 race to save the lives of workers trapped in a five-alarm factory fire. Meanwhile, Maddie reveals a painful family secret that causes Buck to confront his childhood and answer why he is the daredevil he is today.

A going-away party for a bank manager turns into an emergency, and then a mystery, as the first responders are accused of pulling off a daring heist.

The members of the 118 rush to the site of a hit-and-run that leaves a familiar face in critical condition. Meanwhile, with Buck's help, Athena investigates the case of a missing woman last seen in a casino and Josh recalls an emergency in 2006 that led him to become a 9-1-1 operator.

When it finally looks like Hen and Karen may get their foster license back, they are hit with another obstacle. Meanwhile, the 118 races to the aid of a Cheerleader involved in an infield collision.

The 118, still reeling from their recent loss, is dispatched to a mass casualty event after a high-rise apartment building collapses. Then, Athena and Chimney have to work together to save a familiar face.

Look back at how Chimney joined Station 118 and became the firefighter and paramedic he is today.

After a mysterious death, Hen and Chimney put their lives in danger when they suspect that someone is playing God to make themselves look like a hero. Meanwhile, Eddie visits Texas, where he attempts to reconcile with his father.

The first responders deal with a calamity at a chocolate factory; a mail bomb explosion; Eddie receives some surprising news from Shannon; Maddie contemplates her future in the call center.

The 118 springs into action when a city-wide blackout and a record heatwave causes mayhem in Los Angeles. Meanwhile, Chimney confides in Hen about Maddie's condition, and Athena's worst nightmare comes true.

While in Florida caring for her ailing father, Athena and Bobby investigate the disappearance of her childhood friend from 45 years ago.

Athena enlists the 118’s help when a teenager speeds out of control on the freeway. Meanwhile, a routine traffic stop uncovers a shocking kidnapping and Buck struggles with his recovery.

Bobby Nash decides to move to Los Angeles in the hopes of restarting his life after a devastating tragedy that struck his family back in Minnesota, but in Los Angeles, he first meets Athena Grant and works his way to captain of the 118.

Athena is tasked with safely delivering a prisoner to testify on a high-profile case. Meanwhile, a light plane is hit by a swarm of bees and sent careening into a passenger plane.

In part one of a two-part episode, the 118 is called to a research lab that has been set on fire and becomes a biohazard.

A series of ransomware threats leads to an overabundance of emergencies for the 118, including a medevac helicopter crash at a hospital and an air-traffic control tower system failure. Meanwhile Athena must revisit her traumatic attack when the case of the realtor serial rapist goes to trial, Eddie suffers a health scare and Maddie's postpartum depression worsens.

The first responders take calls to help an unusual domestic disturbance, a "death" at a psychic's and a horrific motorcycle crash. Meanwhile, Bobby dips his toe into the dating pool, Abby takes a walk down memory lane, Buck is confronted by his past actions and Athena tries to start her new life.

Athena investigates a mysterious murder during a neighborhood block party and the 118 rush to save lives endangered by a bomb threat. Meanwhile, Chimney has a hard time keeping secrets when Maddie and Buck's parents come to town.

On one of the hottest days of the year, the first responders feel the pressure as harrowing incidents keep happening around the city, including a road rage accident involving a van full of tourists, an emergency at an auto-repair shop and a grenade. Meanwhile, Buck gets a surprise visit from his sister, and a handsome new hire Eddie jeopardizes Buck's chances of being chosen for a fireman calendar.

The 118 fights an apartment building blaze; Athena's response to an accident call leads to a more sinister crime; Hen performs a risky medical procedure during a televised cooking show; Buck is inspired to reunite with his lost love.

The 118 race to the rescue when a structure collapse at a "happiness convention" traps people under rubble. While on FaceTime with her mom, Athena's father suffers a stroke and crashes through the wall of his house. Hen stretches herself too thin with test prep and her new responsibilities at the 118, while Maddie tries to help new recruit get his bearings at the call center.

Holiday-themed incidents include a shopper pushed over the edge, a woman who is literally having a "Blue Christmas" and a luggage handler accident on a tarmac; Maddie revisits her past to embrace her future; Bobby receives shocking news.

Bobby and the 118 race to save lives after an explosion rocks the hospital where Dr. David Hale is performing surgery. Meanwhile, Michael makes a life changing decision.

As Athena and Hen navigate their way back home, Athena will be forced to confront what it means to live without Bobby.

Upon her return to shore, Athena's son, Harry, finds himself in trouble with the law. Meanwhile, Buck grows envious as Eddie forms a close bond with someone else, and the 118 rescue a woman who's stuck on receiving a rose at an iconic mansion.

Athena and Hen face increasing dangers in space as friends both near and far try to get them home safely. Meanwhile, the 118 continues to help victims of the geostorm and falling debris.

As a geostorm ravages Earth, Athena and Hen's space mission teeters on the edge. On the ground, the 118 battles chaos when technology goes rogue.

As Buck tries to manage the trauma following his kidnapping on his own, May tries to secure her first law internship without the help of her mother.

The 118 must account for every decision made during a recent fire call when the team's actions are investigated for possible mistakes. Meanwhile, Buck works behind the scenes to support his team as he waits to learn if he can return to the station.

The 118's beliefs are put to the test as they respond to emergency calls involving a Jack-o'-lantern and a few more jump scares than they were expecting on Halloween.

In honor of Bobby Nash's sacrifice, the 118 comes together to dedicate the firehouse in his memory. Meanwhile, when a billionaire tech giant is involved in a life-or-death emergency, the team must race to his aid.

Following Hen's firing, Chimney grapples with his decision and how it has affected the team. Meanwhile, a new AI call center assistant, meant to help, has begun to create more complications, and the 118 must intervene.

Athena must revisit a painful part of her past when answering a call for help. Meanwhile, the 118 takes a big step forward.

After a victim of the apartment fire that changed Bobby’s life resurfaces, he searches to make amends. Driven by his need to right past wrongs, Bobby delves deep into memories of his childhood, unearthing moments from his fractured past.

Maddie's return to work proves to be more triggering than expected, as she may have returned too soon. Eddie struggles to adapt to his new surroundings.

When a toddler falls down a pipe and becomes trapped, the 118 must rely on more than their skills to rescue him. Meanwhile, old wounds are opened when members of the 118 race to the aid of a man dealing with a divorce.

The 118 and Tommy are presented with the Medal of Valor for their work on the cruise ship rescue. Meanwhile, Hen and Karen encounter an unforeseen hurdle in their foster care journey, while Eddie's emotional affair develops further.

After years of anticipation, Maddie and Chimney's long-awaited wedding day arrives. However, when the groom mysteriously vanishes, the 118 races against time to ensure he doesn't miss the most crucial day of his life.

Hen's attempts at keeping her mysterious health issues private are starting to impact more than just her physical well-being. Meanwhile, Buck and Ravi decide Eddie needs a night out on the town.

Athena is pulled into a mysterious murder investigation when a man arrives at the station to report his own death. Meanwhile, the 118 races to the site of a car crash involving a mother and son.

Hen and Karen welcome a new addition to their family, while a call unfolds involving a person’s limb that’s taken on a mind of its own. Meanwhile, Eddie and Marisol take a closer look at their relationship, and Buck navigates his new feelings.

As Hen continues to seek out a diagnosis for her mysterious symptoms, her friends and family rally behind her. Meanwhile, Harry hits a wall in his attempts to complete the academy firefighting exam and looks for some much-needed motivation.

The 118 race to the rescues with emergencies at a spin class; in a hair salon and to a husband and wife in a compromising position; Buck discovers new cognitive abilities post lightning strike; Hen and Karen are concerned when they find out Denny has been seeing his biological father behind their backs; Maddie and Chimney enlist Athena and Bobby's help with a suspicious neighbor.

Athena and Buck are in a race against time to rescue the rest of the 118 following the fire in the bio lab.

Bobby and the 118 race to the rescue when an abandoned oil well erupts and causes a massive sinkhole in downtown LA. Athena investigates a 30-year-old cold case involving a casino robbery. Buck fears his relationship with Taylor might be ending, and Hen meets a man from her mother, Toni's, past.

Following the tragic events at the lab, the 118 must come together to lay their fallen hero to rest. Meanwhile, despite her own grief, Athena re-investigates the death of a child to help a grieving mother.

As Buck's life hangs in the balance, he dreams of a world where he never became a firefighter, for better and worse.

The 118 race to rescue two roommates desperately trying to find a needle in a haystack at a landfill, and help a woman whose nightmare dream suddenly becomes a painful reality. Athena and Maddie team-up to find a missing boy in a crowded mall; Chimney debates if the time is right to propose to Maddie.

Following the devastating fire at the Nash home, Bobby's fate remains uncertain, while Athena embarks on a mission to uncover the truth. Meanwhile, Hen and Karen engage in a heated custody battle, while Christopher grapples with forgiving Eddie.

A man over-exerts himself exercising; a groundskeeper is cut by his chainsaw. An explosion occurs at a retirement community. May gets an emergency call from a suicidal teen.

Maddie and Buck are blindsided by some unexpected news that turns their world upside down. Meanwhile, Buck and Eddie head to Nashville when they are selected to participate in the national firefighting games. The crossover continues on 9-1-1: Nashville S01E12 Spirit of the Games (II).

Athena and Bobby set off on their honeymoon cruise, but when duty calls, their vacation is put on hold. Meanwhile, a fighter jet traps a civilian, and an unusual incident leaves a couple stuck together.

Harry's first day as a probie proves to be more challenging than Chimney expects. Meanwhile, Eddie and Hen are called into court over a former patient that brings back some old demons.

Athena, Bobby and the 118 "speed" to the rescue to save a family whose pick-up truck has been rigged with a pipe bomb which will detonate if the vehicle slows under 55 miles an hour. Meanwhile, Eddie has a rough transition into his new job, Buck makes an impulsive relationship decision and Hen is reluctant to accept her new partner in Chimney's absence.

Things get messy for the 118 following a massive pipe explosion. Meanwhile, Athena investigates the brutal beating of a man found behind a grocery store, and Bobby's working relationship with Brad from "HOT SHOTS" just got a little more intimate.

After the 118 responds to several calls from the same person, Hen steps in to offer them advice. Meanwhile, Eddie confronts his parents and takes a big step in his relationship with his son.

The 118 responds to a viral stunt gone haywire, a disaster at a couple’s fishing trip and an epic first date fail. Meanwhile, Athena investigates a woman who doesn’t remember being shot in the head and Eddie is forced to have a difficult conversation with Christopher.

The 118 responds to a call at a megachurch, where Bobby runs into his estranged mother. Buck is looking to expand his social circle now that Eddie has left.

Maddie and Athena investigate a case surrounding an abducted mother and child as Hen and Karen learn more about Mara’s family history. Meanwhile, Eddie grapples with unresolved feelings for someone from his past.

When Athena is assigned a rookie to mentor, she begins to question her own abilities. Meanwhile, Bobby and the 118 return to the set of "HOT SHOTS" following a 911 call.

The members of the 118 are called to series of emergencies around Christmas Eve. Then, Eddie struggles with an emotional Christopher.

The 118 race to the rescue at a renaissance faire, then an office building when an overbearing boss is poisoned. Athena fears for May's life when she encounters a disturbed young man. Buck babysits Jee-Yun as Maddie and Chimney begin house-hunting. Eddie and Carla prepare Christopher for his first school dance.

The 118 race to the rescue at emergencies at a commercial bakery and a bodybuilding competition; Bobby's annual performance reviews sends Chimney to the firefighter academy where he runs into a familiar face; Eddie's aunt gets involved in his personal life; Maddie helps a nervous teen suffering a panic attack.

The 118 race to the rescue at emergencies when a fire breaks out in an accountant's office and a car crashes into a "living funeral." Athena is shocked when a suspect dies in her custody minutes after she arrests him; Buck is attracted to a death doula; Maddie and Chimney panic when they are audited by the IRS.

Buck is faced with his past after an electrical emergency call. Meanwhile, Maddie learns to navigate her working relationships now that she has become a supervisor.

The members of the 118 race to rescue a man who claims he was carjacked, shot and buried alive. Then, they arrive at a home where the owner thinks her roommate is a ghost, Hen receives a visit from the past, and Athena and family are concerned that Harry is still haunted by visions of Jeffrey.