Renée Zellweger's boyfriend Ant Anstead asks her to 'please leave the wardrobe at work' ahead of 'The Thing About Pam' premiere

• Ant Anstead asked girlfriend Renée Zellweger to "please leave the wardrobe" for her show "at work."
• Zellweger wears a bodysuit and prosthetics as convicted murderer Pam Hupp on "The Thing About Pam."

TV host Ant Anstead asked his "smoke show" girlfriend Renée Zellweger to "please leave the wardrobe at work" in an Instagram post, referring to the fat suit she wears to play Missourian and convicted killer Pam Hupp in the upcoming NBC drama "The Thing About Pam."

The fictionalized crime show based on true events will tell the story of Elizabeth "Betsy" Faria's (played by Katie Mixon) murder and how her friend Hupp almost tricked a small-town into believing Betsy's husband Russ Faria (played by Glenn Fleshler) actually committed the crime. When they eventually dig into Pam's background, authorities find she has plenty of secrets hidden.

Zellweger previously told Entertainment Tonight that she wore the controversial bodysuit and prosthetics and spent hours in the makeup chair transforming into Hupp because "the idea is to be accurate."

"Especially in the case of telling this story it was really important to as closely resemble Pam Hupp as we possibly could because she seems so familiar," the "Bridget Jones's Diary" star said.

She noted that people "projected" who they thought Hupp was onto her, which is a key piece of telling the story. Zellweger's felt her physical transformation was required to make the story feel true.

Zellweger told ET she was "amazed" the first time she saw herself in her full costume as Hupp.

She said that when it comes to resembling a real person on a show like "The Thing About Pam," one usually expects the costume to get "a couple of things" right, but she had "no expectation" that it would be "as remarkable" as it was.

The "Judy" star said her time in character on-set in New Orleans was "hot" but that it was "amazing to watch" the prosthetics designer do his work. She added that the designer had focused on nailing precise details "right down to the last little freckle."

"The Thing About Pam" premieres Tuesday, March 8 at 10 p.m. ET on NBC.