9-1-1 fans were left shocked on Monday when the Fox show returned after its winter hiatus and beloved character Evan 'Buck' Buckley was seen cheating on his girlfriend with new firefighter, Lucy Donato.
Buck (played by Oliver Stark) and Lucy had teamed up for a daring rescue and they later celebrated together with the crew of the 118. Newcomer Lucy (Arielle Kebbel) - who was a member of Firehouse 146 and was introduced with a reckless devil-may-care attitude, reminiscent of an earlier Buck - then came on to Buck and he kissed her.
WATCH: 9-1-1: Buck gets surprised with a new crew member
Fans were surprised to see the character, whose development has always been based on a desire to not feel alone after a traumatic childhood, treat girlfriend Taylor Kelly in such a way, but now show runner Kristen Reidel has admitted that the kiss was a "symptom of a larger problem".
"He was a little unmoored after Maddie and Chimney left, and he turned to Taylor in that sadness, and that relationship progressed a little faster and in ways he hadn’t planned on," she shared with TV Line.
MORE: 9-1-1 Lone Star’s Gina Torres joins Rob Lowe and Angela Bassett for Super Bowl party
Exclusive: 9-1-1's Oliver Stark reveals 'huge wrench' may tear apart Buck and Taylor's romance
"Buck is the guy who always wants to make it work out. He’s never been the guy who leaves first. So when Lucy comes along, he really likes her, but that kiss is as much about Taylor as it is about Lucy."
The return of the show comes as bosses have also begun discussing the series' timeline, although it looks like there's nothing to fear just yet.
Lucy has shaken up the 118 - and the fans
"We’re not doing Breaking Bad, right? Breaking Bad is like a Russian novel, it has a starting point and it has a natural terminus; whereas something like this, you could bring in new characters and kind of rejuvenate the cast, and as actors are ready to move on, you can end their stories, tragically or triumphantly," Tim Minear told Variety.
"There are ways to cycle in new generations, as we’ve already proven. But I don’t see why it has to end. I mean, we can’t go on forever — but the shows could."
Oliver Stark has already opened up about what to expect from season five of the hit show, and was full of praise for his co-star Ryan Guzman, who plays Eddie Diaz, saying: "I have to say he does some really amazing work in the back half of this season."
\Read more HELLO! US stories here
Like this story? Sign up to our HELLO! newsletters to get other stories like this delivered straight to your inbox.