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Bridgerton Season 3 star Nicola Coughlan was “completely and utterly terrified” about filming Penelope Featherington’s first kiss with longtime crush Colin Bridgerton (Luke Newton). It’s also Penelope’s first kiss ever. “I felt like a teenager,” she tells Tudum. “I felt like when I was about to have my real-life first kiss. That didn’t happen on-screen, which I’m really glad of.”

She and Newton, her co-star and friend, practiced the Episode 2 smooch with intimacy coordinator Lizzy Talbot ahead of filming. “[The stress] just had been building up,” Coughlan says. “We’d known for four years that we were getting to this point … [I was like,] ‘What if I’m a horrible kisser?’ ”

But, as Bridgerton fans know, Coughlan had nothing to worry about. In fact, Kathryn Drysdale, who portrays Mayfair modiste Genevieve Delacroix, heaped the highest praise on Coughlan and Newton after a cast screening. “She was like, ‘It’s the most beautiful on-screen kiss,’ ” Coughlan says. “I was like, ‘Oh my God, thanks.’ It really looks lifted out of a romance novel.”

Although Penelope and Colin have had undeniable chemistry since the beginning of Bridgerton, that kiss changes their relationship. Suddenly, it’s not just Penelope who sees the potential in a romance between these two friends. Colin’s point of view — to reference one very special Episode 5 pop cover — is quickly, overwhelmingly consumed with the idea as well. It’s the first physical step that leads Polin, as they’re lovingly called by fans, on an unforgettably passionate romance in Bridgerton Season 3, Part 2, now streaming.

“This season is a beautiful tribute to the wallflowers of the world,” says executive producer Shonda Rhimes. “It’s wonderful to watch Penelope become who she is and who she deserves to be. And Colin, he’s as much of a wallflower as she is, really.”

Watch Nicola and Luke Discover Penelope and Colin’s Astrological CompatibilityIs it mere coincidence or is their romance written in the stars?

At the start of Season 3, Colin returns to Mayfair from what Newton believes was his character’s first taste of traveling alone. Colin is determined to follow in the footsteps of his rakish older brothers Anthony (Jonathan Bailey) — who is now happily married — and Benedict (Luke Thompson), along with the other merrymaking men of the ton. But Colin finds these fleeting experiences wanting.

“One summer of hanging out and spending some time in brothels and he’s like, ‘No, this is not for me,’” Newton says. “His ‘rake time’ is really short-lived.”

Because, by Episode 4, Colin realizes he doesn’t need to be the kind of man society expects him to be. He needs Penelope. “Penelope is the key, because she keeps him grounded. She keeps him the person that he truly is,” Newton says. “As we continue with the show, we’ll get to see them develop into their relationship and see each other in the goofy or cute little moments that maybe his older brothers are not as willing to publicly disclose.”

We also get some steamy moments. While Episode 4’s carriage scene took the internet by storm, Part 2 delves even deeper into the couple’s passion. As Coughlan once promised Tudum, “Fans are going to lose their minds.” She was telling the truth. Episode 5 features a new take on the highly anticipated mirror scene from Romancing Mister Bridgerton, the Julia Quinn novel that inspired Season 3. In this version, Colin and Penelope — fresh from their engagement — begin to get more acquainted with one another in what will become their family home. Then they move to the chaise lounge.

Showrunner Jess Brownell beams with pride — and “responsibility” — while talking about these scenes. “There’s laughter and there’s this sense of, ‘Oh my God, I can’t believe this is happening. I have so much love for you as a friend,’” Brownell tells Tudum. “Of course there’s that sense of discovery and newness as well. In the carriage ride, in the time they first have sex, the joy there is a powerful thing to show on television: that intimacy can mean comfort and joy and friendship.”

Coughlan is thankful she filmed these moments alongside a friend like Newton. “He’s a dream co-star, and an even more dream romantic lead,” she says. Although it could’ve been “scary” to perform an intimate scene with someone you’re so close with, that wasn’t the case here.

“It made it more terrifying to go into but way better to come out of, because we could talk about it, and we could make jokes about it,” Coughlan says. “We were very lucky in that we got a big say in how we wanted it to be shot and what we wanted to do — and even add certain things we thought would be good. So you feel like you have a hand in controlling it, which is invaluable.”

Despite Colin and Penelope’s Part 2 “love bubble” — which is filled with sweet dances and lengthy declarations of pure love — they also encounter their share of problems. Penelope’s Lady Whistledown-sized secret hangs over them. But there’s also a deeper, more emotional crisis at hand. Once Colin learns about Penelope’s scandal-sheet alter ego, he becomes unsure of how to contend with the ton’s most “badass” author, as Brownell calls her — and what his bride’s success means to his own writing career.

Newton enjoyed seeing his character “squirm” for a few episodes. “Colin feels like he’s way more experienced than Penelope,” Newton says. “Suddenly the coin is flipped. Penelope has all the power because she’s the most famous writer in London, and everyone’s waiting on her every word. He needed being brought down a peg or two.”

However, in the finale, Colin admits that he loves Penelope for being Lady Whistledown. He realizes he feels lucky to stand by her side and “soak up even a little bit of [her] light.” Rhimes credits Brownell with pulling off the latest great romantic speech in the Bridgerton canon. “She really wrote the heck out of all those scenes and really brought some dimension to all of that,” she says. “The idea of whether or not Penelope is going to continue her work — and continue to be the person she’s known herself to be — is fascinating. It turned out so wonderful.”

So wonderful, in fact, that Penelope and Colin get their happy ending at the close of Season 3. As we say goodbye to Polin, they’re married, in love, and the proud parents of a bouncing baby boy … who also happens to be the heir to the Featherington name.

“Luke and I fight about the baby’s hair color. I want a ginger baby. He wants a dark-haired baby,” Coughlan says. “They’re so cute. It would be just so funny to have a little ginger baby in the little Regency clothes.”

But Polin can at least agree on one thing as they look toward the future: “I want them to just be happy idiots,” Coughlan says. “I’m really excited for them just to be massive nerds, sitting at the edge of the ballroom watching everything that’s going on.”

Now that’s the kind of news that would catch the eye of Lady Whistledown — or should we say Penelope Bridgerton, society columnist?