The following contains spoilers for Seasons 1-5 of 9-1-1. This article also contains mentions of suicide.

The first responder show 9-1-1, airing on the Fox network, is an action-packed, character-driven look at the front-line workers in Los Angeles, blending firefighters, police and 911 operators into big event storylines. Known for an entertaining and heartfelt tone with city-wide plots involving earthquakes, tsunamis, mudslides and blackouts, it can be an hour of wild mayhem. Yet, in this complex meld of high-octane stories, humor and emotional feel-good moments, it often delivers a punch of serious issues.

There are, of course, the rescue stories that take a tragic turn, as with the tsunami plot line, but quite a few of the main characters have suffered trauma and ongoing arcs dealing with emotional damage from their stressful jobs and their own personal baggage. Issues of alcoholism, parental conflicts, infidelity and even dealing with the death of a loved one have tested beloved characters such as Bobby, Buck, Eddie and Hen. And it looks as if fan-favorite Eddie is heading for more trouble as his emotional state is on the edge. If previews are any indication he’s going to therapy, possibly to deal with unresolved grief or PTSD.

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Eddie wouldn’t be the first character to seek professional help, either. Most recently, a storyline focused on the character of Maddie, portrayed by actress Jennifer Love Hewitt, as she struggled with postpartum depression and a suicide attempt. Already a survivor of domestic abuse, the aftermath of her actions led her to the care of doctors and an extended absence from her family. In Season 5, Episode 12, “Boston," showcases her treatment: getting a proper diagnosis, medication, and therapy. It’s a detailed look at her progress in getting well and doesn’t pull any punches with Maddie’s pain.

"Boston" also brought in a special guest star, A. J. Cook, Jennifer Love Hewitt’s former Criminal Minds co-star as another patient. The two bond during group therapy, over their mutual motherhood, and being away from their children. And when Maddie’s finally reunited with her young daughter, she loses it, overcome by the time she lost.

Maddie’s story isn’t the first time 9-1-1 has dealt with suicide. In Season 1, Episode 2," Let Go," May Grant, the daughter of police officer Athena Grant, attempts to kill herself, driven to extremes by school bullying. That storyline continues through Episode 3, “Next of Kin,” with child services getting involved, and in Episode 4, “Worst Day Ever,” where the bullies have to deal with Athena’s wrath. And it's revisited in Season 4 when May forgives her bully and must come to an understanding of how her actions affected her mother.

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Another harrowing storyline also involved Athena, after she is attacked and badly injured on the job. In Season 3, Episode 17, “Powerless," she confronts a suspect, is cornered and the gripping drama of the attack is captured over the open police channel. It is a tense and suspenseful moment, intercut with her firefighter husband listening to everything as he rushes to the scene.

Yet, somehow 9-1-1 balances this unflinching view of how dealing with traumatic situations affect people with a very optimistic, even goofy tone. It often leans into the absurd, with some of its rescues being unorthodox. In the Season 4 episodes dealing with a city-wide blackout, zoo animals wander the streets of Los Angeles and the firefighters have a close encounter of the alpaca kind, giving homage to Jurassic Park in the process. Amid all this chaos, though, the well-developed and familiar characters remain the focus and keep the fans watching.

Season 5 of 9-1-1 can be seen Mondays on Fox.