When a smug, male co-worker and rival for a promotion tells Jennifer Lopez, out loud and with witnesses no less, that getting the job won’t be easy “for a woman your age,” you know Second Act promises the kind of workplace comeuppance fantasyland that fueled Working Girl and Lopez’ own Maid in Manhattan. And you definitely know J Lo is going to land that job.

The only question remaining is, at what cost? That’s the premise of director Peter Segal’s new comedy from STXfilms. Lopez stars as Maya, “a 40-year-old woman struggling with frustrations from unfulfilled dreams,” as the logline puts it.

“I just wish we lived in a world where street smarts equal book smarts,” Maya tells the pal (Leah Remini) who will soon join in a plot to upgrade Maya’s resume and social media history, with Maya none the wiser. Fake photos with Obama,...