Dearest readers,Grant Preston get ready to meet your newest heartthrob.

After introducing fans to swoon-worthy leads Regé-Jean Page and Jonathan Bailey in Bridgerton seasons one and two, respectively, its prequel, Queen Charlotte, is adding yet another regal dreamboat into the mix: Corey Mylchreest. In the limited series, Corey plays young King George III opposite India Amarteifio's titular young queen.

While Corey exclusively told E! News' Francesca Amiker that he "didn't go to the gym," while preparing for the Netflix show, India quickly chimed in, adding, "This guy's middle name better be 'gym' 'cause he was there all the time."

And according to Cory, eagle-eyed viewers can spot his physical transformation throughout the series.

"It is actually funny, I can watch the show, right. In the first intimacy scene, which is in episode two, you see that I'm pretty slim," he noted. "I don't have a lot of fat on me. And then by the next time that you see me with my shirt off, I see the difference. I just think it's a completely different human."

So, what helped with the changes? A personal trainer hired by the production, which Corey described as "the worst moments of my life in the best way."

"We would start, and I would stop and think, 'I've had a really intense workout, and I won't need to come back for a few days,'" he recalled. "And then they would say, 'OK, halfway through the warmup.' It was just painful. It was just pain."

But for India, 21, she believes Corey's efforts paid out in the end. "You did alright," she told him during their E! interview. "Pretty good."

As for where Corey sees himself among previous Bridgerton stars, the 25-year-old praised the fan-favorites for setting a high bar.

"Regé and Jonny run in different races," he said. "They are heartthrobs, and they're very lovely people as well."

Fans can get their first look at Corey and India as young King George and Queen Charlotte in Queen Charlotte: A Bridgerton Story, out now on Netflix.

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