June Osborne is back.

On Wednesday, April 8, Hulu dropped the first three episodes of The Testaments, a new Handmaid’s Tale sequel series, in which Elisabeth Moss reprises her beloved character, giving fans a glimpse at June’s life after escaping Gilead.

“She didn’t want to hang up her cloak, as she says,” showrunner Bruce Miller tells PEOPLE. Miller was the showrunner on Handmaid’s Tale too, and he says Moss, 43, has “been my creative partner since the beginning.”

“Before there was a second script [for Handmaid’s] we spoke… Certainly before I talked to Margaret Atwood. And she went from being an actress and producing the first season, to being an executive producer with me and Warren [Littlefield], and the creative force behind the show, and the star and executive vice president in charge of acting,” Miller says. “She’s integral.”

“She would’ve been central to this show anyway, even if she wasn’t in it. But I think she was very eager to come back,” he says.

Elisabeth Moss in “The Testaments”.

Fans first see June as an observer, as she watches Daisy (Lucy Halliday) interact with her parents in their vintage store in Toronto. June reappears after Daisy’s parents are murdered, and informs the teenager that her parents were involved in Mayday, the secret resistance group working to take down Gilead.

It’s a complete shock to Daisy, who has grown up in normalcy and quickly sees her whole world turn upside down. The stakes are raised even further when June reveals that Daisy was born in Gilead and smuggled out into the care of her parents, who were then murdered for their involvement in the rebel group’s efforts.

Miller says having Moss “back on camera” wasn’t always something he felt he could bet on for the new series.

“I think it would always have been my desire. A lot of those things end up being practical. And not only is Elisabeth Moss quite a busy producer, she’s also quite a busy actress and quite a busy director,” he says.

“But in terms of Handmaid’s Tale — when you get to the end of Handmaid’s Tale, I think you feel that [June] has won some great victories and not won some great victories. I think you feel like she has more to do and have a sense of what she would be doing,” he continues.

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Chase Infiniti and Lucy Halliday in “The Testaments”.Russ Martin/Disney 

Still, it was important that The Testaments be able to stand on its own feet. “Although The Testaments is its own show and you don’t have to watch The Handmaid’s Tale [to understand it], and even if you don’t know anything about a Handmaid, I wanted it to be very user-friendly — there are things from the other show that add scale to it,” Miller says.

June’s return is one of those elements. “I think the character of June, being able to hold onto her and have her in this story, was very helpful for me to build and make the decisions with all the other characters,” he admits. “And it’s hard at the end of a long run on a show to let it go. I mean, it’s impossible for me, and she’s had to do it a few times. So I think she’s happy.”

Moss, who also currently stars in the Apple TV thriller Imperfect Women, has played coy for months about whether she reprises her character in the new series. When asked about it on The View in March, she told the hosts: “I couldn’t tell you if I was.”

Working on the series as a producer, though, was “really, really cool,” she said. “And it meant I didn’t have to say goodbye to the world, which I was very happy about.”

The first three episodes of The Testaments are now streaming on Hulu, and new episodes drop Wednesdays.