I was watching TV the other night when I saw briefly part of a promo for something called “The Thing About Pam.”

Here’s the thing about that: I caught one glimpse of that actress’ face — and I didn’t buy for even a second that this was a genuinely fat person.

I grew puzzled when I learned it was Renée Zellweger — an actress who was happy enough to bulk up for her starring role in “Bridget Jones’ Diary” and once again for a sequel. But not for this project as a real-life murderer who escaped detection for many years.

What makes it all so much worse is that Zellweger has an absolutely bonkers explanation for her choice. According to an AP article, “The two-time Oscar winner chose prosthetics this time rather than to gain weight because her character is a real person whose looks, Zellweger believes, factored into why she was initially not a suspect … Zellweger says to match (the murderer’s) appearance this way left nothing to chance. ‘I know the results of a “Bridget Jones” experience and this is not a fictional character who’s up to my interpretation and just seeing what happens.’ ”

Zellweger’s got it exactly backwards, given that I spotted in a literal split second that the face in that promo had been made to look fat in a way you’d never find in nature.

And it’s infuriating when you know that there must be hundreds — thousands! — of genuinely not-skinny actresses literally lining up to be cast in something like this. Women who are probably just as good if not better at the acting, without having to overcome the handicap of completely artificial, unbelievable looks.

“Why does this bother you so much?” my husband asked me. “You didn’t agree when critics wanted darker-skinned people in the movie “In The Heights.” Is it just because this hits closer to home?”

“What do you mean? Are you saying I’m fat? Do I look fat in this column?”

Silence. He had left the room, the coward.

But he might have a point.

It is making me reconsider my skepticism of Sarah Silverman, who made a big point recently of protesting what she calls “Jewface.” “There’s this long tradition of non-Jews playing Jews,” Silverman says.

Silverman’s complaint, first voiced on her podcast, centered on Kathryn Hahn being chosen to play Joan Rivers; Felicity Jones playing Justice Ruth Bader Ginsburg; and Rachel Brosnahan playing “The Marvelous Mrs. Maisel” — shiksas playing Jewish women, all.

Mind you, Midge Maisel is one of my guilty pleasures. My only problem with her is that I’m jealous of how funny she is. But maybe Silverman has a point.

Certainly, I understand that “black face” is not OK. It never really was. It is both politically unwise and morally wrong to cast whites as members of other ethnic groups — especially when there are so many gifted African-American, Asian, Native American and other minority men and women who could be wonderful in those roles.

Authenticity in casting extends to handicaps as well partly because handicapped people need the work, but also — the larger point — because it makes for a better work of art.

“CODA,” one of this year’s 10 Oscar nominees for Best Picture, is a shining example of how this can be.

CODA, which stands for Child Of Deaf Adults, is the story of Ruby, the only non-deaf member of a fishing family in Gloucester, Mass. Ruby’s choir teacher helps Ruby discover a gift for singing and suggests she compete for a scholarship to Berklee College of Music,  but her family hasn’t the slightest understanding, either of her gift or of where it might take her. All they know is they need her as their go-between with the hearing world, even as she protests “I can’t stay here and be your free translator for the rest of my life.”

This film rings true on many levels. It is full of truth, and heart, with a message about the uplifting importance of love for us all. The brilliant non-hearing cast are integral to that success.

When Eddie Murphy puts on a fat suit to play one of his own seven different characters in “The Nutty Professor,” I can understand that that’s his gimmick — his “schtick,” to use a phrase Silverman would understand.

But Renée Zellweger deciding that wearing a fat suit and prosthetics is more truthful in portraying a fat woman than it would be to just give the job to somebody fat?

Nope. Taking a leaf from Sarah Silverman, I’m going to call it a case of “Fat-Face.” And I’m not OK with it at all.