Chicago Fire Season 12, Episode 8 (“All the Dark”) was packed with emotional farewells.

Some incredible first responders have graced the halls of Chicago Fire’s Firehouse 51 — and while some stick around for the long haul, others spend time at the station for a short while, collecting invaluable life lessons along the way.

This was the prime topic in Chicago Fire 12, Episode 8 (“All the Dark”) after first responders made not one but two powerful goodbyes. Season 12 of the series continues to play with the exciting idea of whether or not a candidate is “Firehouse 51 material.” But who left the firehouse and why? It was an emotional watch as Chicago Fire’s dynamite crew navigated the latest crisis.

Find out everything that happened in Chicago Fire’s March 27 episode, below:

Who left Firehouse 51 in Chicago Fire Season 12, Episode 8?
There were shocking exits in Chicago Fire’s latest: one that was welcomed, and another that was bittersweet. Just as he started to settle into Firehouse 51, Derrick Gibson (Rome Flynn) chose to take a leave of absence to address his ongoing mental health issues. Fans were sad to see Gibson go, but can’t say the same for the other 51 farewell: the dreaded paramedic Jared Lennox (Wesam Keesh).

Why did Jared Lennox leave Firehouse 51?

It was obvious from the get-go that Lennox wasn’t Firehouse 51 material. He instantly clashed with freshly-minted Paramedic in Charge Violet Mikami (Hanako Greensmith), questioning her orders and undermining her authority at several points on his first day. To make matters worse, he filed a formal complaint with the CFD about Firehouse 51’s neglect of protocol, which is virtually always reserved for emergencies when a civilian’s life is on the line.

Lennox brisked at 51’s bending of protocol while failing to understand it’s the key to the station’s success. 51’s ability to discern when and how to get flexible during a crisis has saved countless lives, but Lennox failed to see that.

It was an awkward return to 51 for Lennox after he filed a complaint against several members of the station. When the firefighters weren’t forced to walk on eggshells around him, fearful of another complaint, they found themselves unable to relate to the guy who joined their ranks with ulterior motives. Frankly put, 51 doesn’t take kindly to a snitch.

Violet particularly struggled to work with Lennox after her recent promotion to PIC. Lennox explained that he knows playing it by the book doesn’t win him any popularity contests, but he is proud of his honest work. Violet shrugged him off, but an intense paramedic call led Lennox to swallow those words.

Violet and Lennox arrived at a motorcycle bar to find a man in desperate need of a hospital. Lennox attempted to cut the biker’s leather jacket to treat him, earning him a scolding death threat. Violet, always great on her toes, identified a solution that would allow the jacket to be salvaged. As they put the patient in the ambulance, Lennox was too afraid to ride in the back with the biker, as protocol demands. The cowardly Lennox asked Violet to make an exception and allow him to drive.

“Are you asking me to break protocol?” Violet quipped.

“Well, yeah, but for good reason,” Lennox said, earning a wry look from Violet. “You know what I mean. It’s just temporary, anyway, please.”

“If you’re scared, I’m not gonna force you to ride in the back,” Violet said, making her point clear. “Because your safety and our victim’s safety is more important to me than protocol.”

Taking the keys with his tail between his legs, Lennox got the point. Between the workplace tensions and Lennox’s rough indoctrination into 51, Chief Wallace Boden (Eamonn Walker) pulled the plug on Lennox, placing him back in the CFD floater pool by the episode’s end.

Why did Derrick Gibson leave Firehouse 51?
While fans were happy to see Lennox leave the firehouse, Gibson’s exit was sad. His storyline shined a spotlight on the long-term consequences of trauma. Gibson left Firehouse 51 after his drug addiction made its way into his work life, prompting a nervous breakdown and his decision to leave.

It began in Season 12, Episode 5 (“On the Hook”), when viewers learned he was a former competitive boxer, but his career ended after one of his punches led to an opponent’s death in the ring. Gibson skirted any legal consequences; however, after meeting a high school basketball player going through similar circumstance on a 51 call, he began unraveling.

Gibson confessed to Sam Carver (Jake Lockett) that after failing to cope properly with the end of his boxing career, he suffered a nervous breakdown, leading him to spend a stint in a psychiatric unit. Eventually, he became a firefighter to create distance between himself and his inner demons, but in “All the Dark,” we saw how ignoring his problems only led to more trouble.

Gibson had been absent from shifts for a few days, prompting Carver to give his new friend a check-up after he returned. Gibson dodged his question while claiming to have the flu going around, but Carver was quick to pick up on Gibson’s erratic behavior. Gibson was impatient and irritable, later snapping at Lennox and calling him an idiot in front of the entire station. After Gibson’s behavior went from troubling to downright suspicious, Carver correctly guessed Gibson’s issue: He was abusing prescription drugs.

Carver confronted Gibson, telling him he knew he was abusing prescription drugs and reminded him that he was not the only one with demons. Carver told him to pick himself up off the floor and pull himself together. After Carver left, Gibson took it hard, slamming his fist into a locker and injuring himself.

The altercation was enough to catapult Gibson into the throes of a panic attack. After following a blood trail to the restroom, Stella Kidd (Miranda Rae Mayo) found her Truck 81 recruit trying to stabilize himself. When Stella asked if he was OK, Gibson struggled to get any words out.

“I thought I pulled it together,” Gibson said before adding, “I need to get out. I need to go.”

Stella was sad to see one of the members of her truck leave, but Gibson’s wake-up seemed to be exactly what he needed.

Watch Chicago Fire on Wednesdays at 9/8c on NBC and the next day on Peacock.