A prime example is the new Netflix chase-comedy “The Lovebirds,” starring Hollywood darlings Issa Rae and Kumail Nanjiani as a pair on the run from the law — and a killer. Likable though they are, their distinct comedic personalities don’t gel at all.

Rae, a fun-loving everywoman, is best-known for creating and starring in the terrific HBO series “Insecure,” while the awkwardly observational Nanjiani co-wrote and starred in the Oscar-nominated “The Big Sick.” Both of ’em are swell, but in “The Lovebirds” the actors are, to borrow a popular new phrase, alone together.

Most of their scenes come off as low-stakes dueling stand-up routines, rather than a plot that builds. Nanjiani will wax poetic about why restaurants give customers a sidecar of extra milkshake, while Rae privately spazzes out on her phone across the table. They land some punchlines, but act like there is Plexiglass between them.

They play a New Orleans couple, Jibran and Leilani, who after being together four years, can’t stand each other anymore. In the car on the way to a party, they dramatically break up, when all of a sudden their car is hijacked to commit a murder. Looking guilty as hell, the two flee the area, and spend the rest of the movie trying to figure out who was responsible and clear their names. Yada yada.

Sound familiar? There are so many movies about boring professional adults getting roped into an evening of crime. “Date Night,” with Steve Carell and Tina Fey, and “Fun Mom Dinner” jump to mind. Few of them are any good, but a recent standout was 2018’s “Game Night.” Without anything clever to add to the pattern, “The Lovebirds” functions only as a showcase for Nanjiani and Rae, who already have far better showcases.

Was director Michael Showalter’s wrist slapped by a nun? The brilliant guy gave us the irreverent cult comedy “Wet Hot American Summer” and the millennial send-up sitcom “Search Party.” This film is militantly obedient by comparison, even its over-the-top “Eyes Wide Shut”-style ending.

Granted, not every comedy must obliterate the ground with guts and innovation, but the biggest failure here is pure believability. When a gun is pointed in your face, you should be afraid of that gun. When you are knocked unconscious and tied to a chair, you should perhaps be a bit shaken up by being kidnapped. Showalter’s characters behave so naively, like the Ohioans of “The Out-of-Towners,” but Jibran and Leilani are savvy urbanites played by intellect-based humorists. Acting like idiots makes no sense.