Niecy Nash-Betts couldn’t have anything nicer to say about her costar — and now friend! — Travis Kelce.

The actress leads Ryan Murphy’s newest thriller series, Grotesquerie, and tells PEOPLE that the Super Bowl champion was “lovely to have on set.”

Grotesquerie, which premieres Wednesday, Sept. 25, marks Kelce’s first-ever scripted role, and Nash-Betts, 54, says he was “very professional” and “always came prepared” to set.

“Travis was very open. He was very open on if there was a note given or a suggestion given. So amenable. ‘Tell me what I don’t know. Tell me what your thought is on this,'” she recalls. “I love that he didn’t come in trying to act like, ‘I know everything and I know it all.'”

Nash-Betts adds how the tight end was “so receptive,” as she notes, “Listen, I love actors and I want you to win. So anything that I could do to help to be a part of helping you create, find moments, dial it in a little bit differently, I was completely there for it.”

“I just think that fans are going to find him very charming in this role,” she teases.

The Emmy winner also reveals who on set was the most starstruck by Kelce, 34, when he joined.

“It was funny because I saw people’s reaction to him before I really could take him in. All the guys — these big guys on the set, the grips, transpo — everybody was just fangirling all the way,” she remembers. “And I’m like, ‘Oh my god, guys!'”

NFL stars aside, playing the role of Detective Lois Tryon in the series was challenging for Nash-Betts, as Lois is not only investigating a “series of heinous crimes” that feel “eerily personal,” per the official description — she’s also battling addiction.

“In this kind of story, you have to track where she is in her addiction,” she says, referring to Lois’ battle with alcohol during the series. “Is she hungover? Is she plastered? Is she tipsy? You know what I mean? Does she want to drink but is she trying not to? There’s so many places to be in it, and so trying to track that, that was difficult.”

Though she’s admittedly not a fan of horror, the Dahmer — Monster: The Jeffrey Dahmer Story star is “obsessed with this show.”

“When we were filming, we would have days where the cast and crew would just be talking on set about who we think Grotesquerie is,” she says. “‘I think it’s this person, I think it’s that person. What about this? What about that?’ You can’t help but lean in, because it is the perfect whodunit.”

Niecy Nash as Lois Tryon in ‘Grotesquerie’.Prashant Gupta/FX

Along with Nash-Betts and Kelce, Courtney B. Vance, Lesley Manville, Micaela Diamond, Nicholas Alexander Chavez and Raven Goodwin also star in the series.

Grotesquerie premieres Wednesday, Sept. 25. at 10 p.m. ET/PT on FX and streams the next day on Hulu.