Mack & Rita has few surprises in its body-switch premise, making a lukewarm comedy out of a familiar concept.

For what is essentially a higher age demographic for Freaky Friday, it’s surprising how mundane Mack and Rita get with its concepts. There’s a lot of potential in trying to make a millennial switch place with a baby boomer. Think of how much funny and meaningful stuff can be done with the idea. Sadly, this film mostly just goes through the motions.

Elizabeth Lail plays Mack, a thirty-year-old woman struggling with her career. Not enthused about attending a wedding for her best friend, she wanders off to a tent where a weird man gives her a chance to reconnect with her past. As she states her problems and grows more frustrated with her life, she is transformed into the seventy-year-old version of herself, played by Diane Keaton. Shocked by this development, she seeks comfort in her friends but tries to make this new identity work for her career and connection with others. She soon adopts the name Rita and poses as a relation to Mack.

Keaton does about as well as she can with this material. She goes through some of the expected reactions to being shocked by her oldness and struts her stuff in the predictable moments of absurdity. Her initial banging on windows, pleading to her friends, and stumbling into pools are parred for the course, but Keaton sells it well. It’s also refreshing to have her play a role where she plays someone learning to find comfort in old age. That’s the route one would expect this film to take, but it’s still a sincere approach despite all the corniness in her many wine-centric talks with her new group of elder friends.

The biggest problem with a picture like this is that it merely spins its wheels trying to find funny stuff to do. Mack’s Rita form will take on everything from absurd yoga, where she rants back at the instructor, to attending a feminist event where she accidentally lights herself on fire. Numerous plot lines seem to resolve all too easily, as when Rita forms a romance with a young dogsitter that somehow continues after the inevitable transformation back into Mack without much issue. There’s also some little contemplation on the passage of time and how living through your forties and fifties can not be as scary when those days are ahead of you. Thank goodness a film like this doesn’t waste time explaining the mechanics of Mack’s transformation.

The film is more admirable for never coming off like a boomer-friendly slam on millennial culture, despite its numerous chances to slip into this lazy humor hole. There’s some back and forth Mack shares as Rita to her old friends about her social media profile and followings, but nothing as tiresome as the questioning of social media or an embarrassing embracement of its lingo. Honestly, if the film had just been Rita having conversations with her eccentric wine group, that could have been a moving picture instead of one that feels desperate for comedy.

Mack & Rita has few surprises in its body-switch premise, making a lukewarm comedy out of a familiar concept. It has its moments of charm, but they are few and far between in a film where it’s expected that Dianne Keaton will carry this humdrum script into something more. She does her best, but there’s only so much an accomplished actor can do with such a lacking script.