Jake Moran’s review published on Letterboxd:
This might be one of the worst films I've ever seen.
Now, I'm sure that most popular series usually come to a point where the creators think, "Are we secure? Can we coast from here on, resting on our laurels? What if we just wrote a bunch of sit-com sketches and threw them together into a movie, giving the audience just what they want? After all, don't they want to watch these guys do the same exact thing over again, but this time with more bickering?" Fortunately, many sagas never reach that point. But Lethal Weapon sure did.
There's barely a plot here. And it's impossible to spot until about 30 minutes into the film since the movie spends so much time indulging in its three leads, showing the audience what everybody "is up to now" (which isn't really any different from where they were the last time). Murtaugh is still trying to retire, Riggs still does reckless stuff that works out for the better, Leo Getz is still trying to keep the audience entertained, Murtaugh's family is still kinda-present but mostly unimportant, etc. And just like the last movie, there's even a nod to whatever's going on in the black community right now, with just enough shallow deference to make you think that the creators actually care about social issues.
Trust me, this one is a slog. Everything that happens is played up just like a bad TV show, where you know exactly what's going to happen and how the characters are going to respond. And the crooked sense of justice within it is on the level of Dirty Harry, but without Dirty Harry's bleak self-awareness (seriously, why do we think it's okay for our cop heroes to torture and threaten their targets?). If you liked Lethal Weapon for the characters, or enjoyed all the times they were mean to each other, than you might like this one. Otherwise, do yourself a favor and skip it.