The new Guy Ritchie movie is exactly like every other Guy Ritchie movie, which is to say it’s a lot like “Reservoir Dogs.”

“The Gentlemen” plays out like variations on a theme, the theme being, “Oh, that’s an interesting way to kill someone,” featuring actors who could be someone’s dream cast for a sequel to “Magic Mike.” Matthew McConaughey, Colin Farrell, Charlie Hunnam and Henry Golding play figures in the London drug trade who double- and triple-cross each other.

We’re meant to find it larky and fun, despite the high body count, because all of the people getting killed are crooks, but that also means we don’t care about any of them. It’s familiar, no-stakes territory for the writer/director of “Snatch” and “Revolver,” but Ritchie does deserve credit for the very clever casting of Hugh Grant, who’s having the most fun he’s ever had on screen, give or take “Paddington 2.”

Grant, using a Michael Caine/“Oy, guvnah” accent that is light years from his usual self-deprecating elegance, plays a sleazy wheeler-dealer who has inside info about the above drug lords.

As the movie opens, he’s telling Hunnam what he knows, disguising his blackmail attempt as a movie pitch. (There are lots of plays on the idea that it’s unclear if criminals are stealing from the movies, or vice versa, including a group of thugs who rob a marijuana farm and post a stylized video of their crime on YouTube.) Alternately unctuous and menacing, Grant steals every scene he’s in, which is uniquely appropriate in a movie whose characters steal everything they see.

It’s also fun to see Michelle Dockery as the tough owner of a (nonsensical) all-female body shop whose fresh mouth would make Dockery’s best-known character, Lady Mary on “Downton Abbey,” chuckle with jealous admiration.

Otherwise, the surprises are few and far between: a high-pitched bullet sound effect I don’t think I’ve ever heard. A gang whose matching plaid tracksuits make them look like a K-pop band. Some impressive projectile vomiting. A soundtrack that — again, à la Quentin Tarantino — resurrects ’60s, ’70s and ’80s gems such as the Jam’s “That’s Entertainment,” Roxy Music’s “In Every Dream Home a Heartache” and Johnny Rivers’ “The Snake.”

How much does “The Gentlemen” owe to “Reservoir Dogs”? Well, I just did an internet search for the latter movie’s trailer and, when I found it, it was preceded by a targeted ad for “The Gentlemen.”

Imitation is certainly not the worst cinematic offense. “Reservoir Dogs” is almost 30 years old and it’s great, so it’s worth paying homage to. But despite its charms, “The Gentlemen” ends up feeling longer than its 113 minutes for one reason: You’ve seen it all before.