9-1-1 returned from its winter hiatus three weeks ago and immediately set the fandom alight when beloved character Evan 'Buck' Buckley was seen cheating on his girlfriend Taylor Kelly with new firefighter Lucy Donato.
Exclusive: 9-1-1: Lone Star actor Ronen Rubinstein shares what he really thinks of TK’s 'traumatic' storylines
The scenes saw fans divided - but British actor Oliver Stark, who plays Buck, has now shared that he was "excited" to see that decision in the script, and doesn't necessarily believe that it was bad character development.
WATCH: Buck gets surprised with a new crew member on 9-1-1
"When I read it I was excited about it because Buck and Taylor (played by Megan West) had become quite domesticated in the first half of season five, and I felt they had plateaued," he told HELLO!
He added: "That's not a bad thing but it wasn't going anywhere at that moment and I knew - because in the world of TV the way things happen is through conflict - the introduction of Lucy and Buck's obvious bad choice would create conflict and I was excited to play those scenes out with Megan."
Exclusive: 9-1-1: Lone Star actor Ronen Rubinstein teases heartbreaking drama with Carlos
As for what the kiss means for Buck and Lucy, episode 13—which airs on Monday 11 April—will see the fallout of their actions as Buck's sister Maddie encourages Buck to tell his girlfriend the truth.
Plus, Buck has to learn to work with Lucy (Arielle Kebbel) after she was introduced as a new full-time member of the 118.
Lucy has shaken up the 118 - and the fans
Viewers will see "a few moments of clear awkwardness" between Buck and his new colleague.
But Oliver teases that they will both "move on" and viewers will see them "learn from each other and use their different experiences to lift the other one up".
And as for Buck and Taylor? Oliver only hints that "there is certainly a big decision to be made" for the couple.
Maddie and Buck will be reunited in episode 13
However, amongst the drama, episode 13 will finally see a reunion between siblings Buck and Maddie.
Episode 12 was a standalone 9-1-1 episode that saw the drama move from Los Angeles to Boston as we discovered what Jennifer Love Hewitt's character Maddie Buckley had been doing since she left her partner and baby in the early half of season five; Jennifer left the series because she was on matenrity leave.
"Jennifer is such a joy, she is such a ball of energy and as a fan of the show and as a person who gets to work with her, she was a real loss from season five," Oliver said when asked how it felt to have the actress back working with them on set.
"I was so excited to have her back, and we fell immediately back into our old back and forth - which for the most part is her poking fun at me and me just loving every second of it."
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.