That 9-1-1: Lone Star Tarlos shocker has actually been in the works since 'the first episode'

That Carlos revelation on the 9-1-1: Lone Star season 4 premiere caught many Tarlos fans by surprise, but actor Rafael Silva has known it was coming all along.

Series co-creator Tim Minear actually concocted that Silva's Carlos had been romantically involved with Iris (Lyndsy Fonseca) — the sister of Liv Tyler's Michelle — at the very inception of the Fox first-responder drama.

"Tim shared that with me when I first started on the show," Silva tells EW. "We didn't have the time or the space to explore that storyline until now, but I've always known it and it justified a lot of who Carlos is, who he wants to be, and why he acts in a certain way. I'm actually quite grateful that I had that little secret."

Rafael Silva on '9-1-1: Lone Star'
Rafael Silva on '9-1-1: Lone Star'

Jordin Althaus/FOX Rafael Silva on '9-1-1: Lone Star'

"Even in the first episode you get some of that information just through the implication that Carlos and Iris were close," explains Minear. "Carlos ended up doing what a lot of young gay people do, trying to conform to what they think is expected of them, and he married his best friend, who was troubled in her own way — although when he married her, there were no signs of her schizophrenia yet."

Minear explains that Carlos never divorced Iris "because he had thought she was maybe dead. When they were searching for her, everybody thought that maybe that's what had happened. And then when she turned back up, he didn't want to divorce her because his health insurance through his job was assisting her. It became a struggle for him, but it's not like he was lying to TK. He wasn't married in any deeply meaningful sense of the word, but now that TK and Carlos are actually getting married, it has to be taken care of."

The season 4 premiere sees Carlos approach Iris at work, and he's greeted by a slap in the face, literally.

"We shot that scene at the end of that day, and I went up to Lyndsy and I was like, 'You can hit me for real. You can smack the s--- out of me.' And she did a wonderful job of smacking the s--- out of me. But that assisted in playing the truth of the moment, which is like, 'I left you.' Carlos has to face the fact that he quote-unquote left his wife, his best friend, the person who gave him everything at a point when he had nobody. He has to take responsibility for the fact that he, pardon my French, f---ed up."

The episode ends with Iris insisting on meeting TK (Ronen Rubinstein) before agreeing to sign the divorce papers, something Minear teases will leave Tarlos in an awkward-but-familiar position.

9-1-1: LONE STAR
9-1-1: LONE STAR

FOX Rafael L. Silva and Ronen Rubinstein on '9-1-1: Lone Star'

"It's not a perfect parallel, but in the same way that Carlos had to understand that he couldn't quite get in between — or completely comprehend — what TK's relationship was with his sponsor last year, this is a similar thing. TK has to realize that Carlos has a history with this woman. And for TK, she may just seem like a spoiler at the moment, but there's a much deeper connection here."

Rubinstein, for one, is excited to see it all play out: "This is just the craziest news for Carlos to give TK," says the actor. "It sort of sets the whole direction of the season for those two."

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