9-1-1 concluded season four with an hour-long episode that saw Eddie Diaz and Bobby Nash end up in hospital, a new romance blossom, and Evan 'Buck' Buckley get some shocking and life-changing news.
Six million viewers tuned in to see if Eddie had died - spoiler alert: he didn't - but the shocks didn't end there as we discovered who had been targeting the first responders and why, if Bobby and Athena Grant's marriage was truly over, and if Maddie Buckley would ask for help as she suffers from postpartum depression.
Oh yeah, and for Buck to rekindle his romance with Taylor Kelly AND be told by Eddie he had named Buck his son Christopher's legal guardian if Eddie were to ever die.
MORE: 9-1-1 star shares sweet behind the scenes memories ahead of 'dramatic' season 4 finale
WATCH: 9-1-1 season four finale promo
Oliver Stark, who plays Buck, breaks down the episode with HELLO! as well as explaining why he quit social media before the finale and what this means for Buck and Eddie moving forward.
How did it feel watching the finale?
It felt really good, I was really intrigued how it would play out because it was a really long script for a 42-minute show so I was impressed with everything they did.
Episode 13 ended with a cliffhanger - were you told in advance Eddie would be shot? When you got the script for 4x13, and saw that final scene, what were your thoughts?
I had no idea what was going to happen! The nature of the show and the scale means we don't get scripts in advance so we got 13 and it was this huge cliffhanger and I think my reaction - and the entire cast - and even Ryan Guzman, was, "wait is Eddie going to die!?"
But it was a real shock for all of us.
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Buck has been on a huge journey this season, and I really worried after Buck Begins where the character would go next. But episode 14 really showed how much more work Buck still has to do for himself.
The things we learned about Buck earlier show there is a lot of deeply-rooted trauma and these are issues that won't go away overnight, or go away in three therapy sessions. They'll only go away with ongoing consistent work.
Buck watched in horror as his best friend Eddie was shot by a sniper
I am always onboard to see the continued growth of Buck, and that's something we have been able to explore in the sense of him starting to quiet the self-deprecating thoughts, but, as in real life, it's one step forward and two back.
He'll feel good about himself one day and then be doubting himself the next.
Buck has been pushing for a romance with Taylor Kelly and we finally saw her take Buck out of the friendzone, where do you see this going?
I do think that there is a certain positive side that they bring out in each other, they balance each other out.
Taylor Kelly and Buck have struck up a friendship and maybe more
He loosens her up and she keeps him on the straight and narrow - most of the time - and then they have these chaotic moments where they fall down the well of madness together!
It's a fun relationship to explore and I enjoy working with Megan [West] so I am happy to see that continue.
In the treasure hunt episode it was great to see the fire fam really begin to thaw to her as well. How important was it for you to see Buck have someone outside of the 118 to lean on?
He had Abby in season one, and then she went away, and we have Maddie but she is, through her relationship with Chimney, connected to the 118 so he had this void that has never been filled for Buck since Abby left.
The show is an ensemble and includes Angela Bassett, Aisha Hinds and Peter Krause
We highlighted that in season three with the experience with the elderly firefighter Red who passed away, when Buck realized: "I don't have a life outside of this, and maybe I perhaps really need one."
But it's only a good thing for him to broaden those relationships and find out who he is when he takes the uniform off.
As part of an ensemble it's really hard to focus in-depth on one character, which is why the Begins episodes have been so clever, but as an actor how do you handle a lack of exposition for Buck or certain storylines?
When I first joined the show - this job was a big deal for me - and those first episodes of season one I had all this great material and then, it's an ensemble show, so that spotlight has to shift character to character.
Peter [Krause] who plays Bobby has become a friend and mentor, and I said: "Do you think I am messing this up? I was getting great stuff, and now I am not."
I was very insecure about that. He sat me down and he was like, "I get it, you're 26, you want to be the one that's always throwing the ball, but sometimes it's nice to sit on the bench," and I've remembered that.
Buck's sister Maddie showed up in season two
The show isn't actually about one character, and that's the strength of the show.
It highlights the different issues that people of different backgrounds and cultures are experiencing going through.
Do you think the addition of Albert will cause a shift in the firehouse and Buck's behavior at work now that there's another young new firefighter to look out for, especially after Buck's talk with Bobby in the finale?
That's an interesting question I hadn't thought about, there's certainly potential for that.
When Albert came into the show and into Buck's life, there was a sense he was a younger version of Buck, going through some of the same issues Buck had dealt with so there is definitely opportunity to have Buck go, "I can be a role model to this guy, and mould him into a great firefighter."
Eddie revealed in episode 14 that he had made Buck Chris' legal guardian months prior. What was your thought process when you read that line, and how will this change things for Buck and Eddie moving forward?
I loved reading that in the script. It's a nod to the connection these two guys have which cannot be denied, there is something really close between them, and meaningful. It's a huge step for someone to take, to trust [someone else] with their heart and soul, their child.
I was really happy to see them take the step, and it's another thing that possibly means Buck next year may be a little more careful.
Buck has become incredibly close to Eddie's son Chris
He's not yet Chris's guardian because Eddie is still very much alive, but if things were to take a turn for the worse, he would have to step in so I wonder if it will change the way he goes about his business.
You are very aware the relationship between Buck and Eddie has become the cornerstone of this show, and showrunner Tim Minear has said he doesn't want to define that relationship any time soon. But as an actor do you feel that at some point soon you want to see some sort of decision made either way about where this relationship actually is, or could be, going?
I really feel for Tim in these moments. I truly believe he is trying to serve the story, the characters, and the audience at the same time and do what he feels is right.
I don't say this lightly but I think he is a genius, I love everything he puts together, so I give myself over to him and give him my trust.
Buck and Eddie's friendship - and chemistry - has become the cornerstone of the show
I understand what he means when he says he writes a scene and they come to life in a way he maybe did not expect when he created these characters, but he is right when he says there is a definite chemistry between the two of us on screen, and we'll see what happens in the coming season.
When did you realize fans were seeing a chemistry between you and Ryan [Guzman]? Has it changed the way you approach Buck, and scenes with Ryan?
I don't think it has changed the way I approach the scenes. The job of the actor is to try and play with the most truthful thing within that moment and take into consideration, even subconsciously, the relationship we have built between us as the characters.
I don't know if there is now a conscious decision made about particualr moments, it's just playing the truth of the moment and then we see that result on screen.
They became fast friends after a strained start
I don't think there was a particular moment when we realized these characters can mean something to each other… maybe at the end of the earthquake episode, when Buck was the one to drive Eddie to pick up Christopher.
Thinking back to that shot of Buck sitting in the car and watching Eddie pick Chris up, and now knowing of Buck's childhood, that is certainly a meaningful moment for him to see that parent child relationship in a way he never quite had.
One word to describe fans is passionate and I know you've struggled with certain factions of the fandom, even leaving social media. How have you been coping with that pressure over the years? Do you have a support system, or speak to any cast members about it?
Not really, and maybe I should because I get caught up in my own head and thoughts about it.
I recently stepped away from social media. I think it's a very intense environment and things can feel heavier or louder than they were maybe intended.
Eddie revealed in hospital he had named Buck his son Christopher's legal guardian if he were to die
I felt no animosity toward any faction of fans - people have every right to make comments or jokes, but I have every right to remove myself from that situation if it doesn't make me feel good about myself.
So it's not a step back forever but certainly for now, the healthiest thing for myself is to put my attention elsewhere.
Over the past four seasons we've had some of the wildest emergencies imaginable, is there perhaps a funny or crazy story you've seen in the news which you think would be fun to act out?
A lot of them tend to be the "Florida man" storylines, and I know [the writers] spend a lot of time on YouTube.
Thankfully that's not my job though, I don't know how they continue to come up with these fresh emergencies, I am happy to be on the side I am!
The show has been running for four seasons and was renewed for a fifth
In the last crossover most of your scenes were with Ronen Rubenstein. Is there a character from Lone Star that you'd love to work with or see Buck interact with next time round?
I don't know how it would work but whenever I watch that show Sierra [McClain's] performance as Grace is... they struck absolute gold [with her], the poise and gravitas she brings to every scene.
I don't know how they would end up [with] a Buck and Grace scene, but if there is any way that can happen I would sit there in awe, I am all for it.
How do you shake off Buck between seasons?
It may sound superficial but I like to not look like Buck. So I'll change my appearance, and that makes me feel a little bit more like Oliver and not Buck.
9-1-1 seasons one to four are available to watch on Hulu.
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