For the second wig, which Elle wore during the sentencing scenes, Jules worked with Ren Studios’ ArjenA makeup artist Todd WatsonTo apply a prosthetic foreheadpiece. “This gave us the ability to show thinness and hair breakage due to Michelle’s drastic weight loss,” Jules said, adding that it took about an hour to get Elle ready.

With the early episodes, the team had to be a bit more creative as there’s less footage available of Michelle from before the trial. Mirren said, “We kind of had to come up with our own version of Michelle and how she would dress and emulate—she’s sort of a chameleon.”

They were aided in their endeavors by Elle, who was an executive producer on the series. Mirren said that the actress was invested in portraying “the small nuances and trying to get as real as possible,” adding that it was “a hard challenge.”

But seeing Elle on-screen made it worth it, with Erin saying, “I’m just so incredibly proud of Elle’s performance.”

See the results of the team’s work when Plainville, Illinois Girl streams Tuesday on Hulu.