The stars plays a 30-year-old influencer who suddenly transforms into her future 70-year-old self. 

What happens when a disenchanted 30-year-old wakes up as a fabulous 70-year-old with style? The answer: Diane Keaton, that's what. 

In Mack & Rita, Keaton stars as Mack Martin, a 30-year-old influencer who reluctantly joins a Palm Springs, Calif., bachelorette trip for her best friend Carla and then suddenly magically transforms into her future self: chic Aunt Rita. Finally freed from her restraints, Rita comes into her own as a "coastal grandmother" social media sensation and sparks a little romance with a younger-ish man.

Staying fab as a septuagenarian isn't the issue for Aunt Rita (this is Diane Keaton — hello!). It's Carla, who wants Mack back in the present for her wedding. To try to make this happen, she urges Rita to drink some mushroom tea, reminding her, "We're flirty, not dirty. We're 30." 

"Don't they make people nuts — like, crazy?" asks Mack, right before guzzling down the entire cup. Watch the exclusive clip below.

And no, your ears do not deceive you. That is Only Murders in the Building star Martin Short voicing Mack's dog and giving her a "very sheik" pep talk.

The film also stars Taylour Paige, Loretta Devine, Amy Hill, Lois Smith, Wendie Malick, Patti Harrison, Addie Weyrich, Aimee Carrero, and Nicole Byer.

Mack & Rita opens Aug. 12 in theaters everywhere.

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