Reba McEntire has been keeping a big secret: She makes a cameo in Barb & Star Go to Vista Del Mar, a new comedy from Kristen Wiig and Annie Mumolo. Now that the movie's available for streaming, however, she's offering fans a behind-the-scenes look at her transformation for the film.

In the movie, McEntire plays Trish, a storm chaser-turned-mythical water spirit with whom best friends Barb (Mumolo) and Star (Wiig) are obsessed. When the two pals from the Midwest head to Vista Del Mar, Fla., for a vacation, shenanigans ensue, and ... well, we're not about spoilers, but let's just say that Trish plays a pretty big role.

"I just wanted to know where, when and what am I going to wear? I was so ready and excited to do it," McEntire tells USA Today. However, she shares, "The script had me diving in[to the water] and swimming off. And I can't dive."

It was an easy enough fix to make in order to get the country star on board, especially after, as the newspaper reports, Mumolo and Wiig wrote McEntire "an impassioned letter" to ask her to take the role.

"She just instantly got it," director Josh Greenbaum tells Entertainment Tonight. "I think that's the thing with this film: Some people just get it [and some people don't] ... but clearly Reba McEntire was a kindred spirit in comedy."

 

 

 

An Instagram post from McEntire shows her mid-hair and makeup appointment, as well as photos of her final look. There's also a few shots of her in the water during filming, still all done up.

"At one point, she shouted at the boats [that were disrupting filming], 'Hey, I’m trying to make a movie over here,'" recalls Greenbaum to USA Today. "I think that’s going in the bloopers."

In addition to Mumolo, Wiig and McEntire, Barb & Star Go to Vista Del Mar also stars Jamie Dornan, Vanessa Bayer, Phyllis Smith and more. While much of the film's all-star cast was advertised prior to its Feb. 12 release, McEntire's appearance stayed hush-hush.

Mumolo and Wiig previously received numerous accolades for Bridesmaids, the 2011 comedy they co-wrote together. The pair met when they were both members of the revered improv comedy troupe the Groundlings, and Wiig is also well known for her time on the iconic late-night sketch comedy show Saturday Night Live.

McEntire, meanwhile, has made a name for herself as an actor in addition to her music career. Most famously, she starred in her own TV comedy, Reba, in the 2000s. The show aired on the WB, then the CW, from October of 2001 until February of 2007.

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