Guy Ritchie’s (“Snatch”) and Danny Boyle (“Trainspotting”) made it all look so easy that Matthew Vaughn (“Layer Cake”) thought he’d have a go.

But that slice of British working class/underclass/criminal class life ensemble dramedy thing is easy to imitate, harder to get right.

“Three Day Millionaire,” scripted by Paul Stephenson and directed by Jack Spring (“Destination: Dewsbury”), is a Ritchie-lite movie that gets many of the basics right even as a misses a couple of the most obvious.

It’s a tale of “trawlermen” from the historic fishing port of Grimsby, a Lincolnshire landmark whose glory days ended as the Cod Wars were settled in the 1970s. A group of sons-of-sons-of-sons-of-sons of trawlermen stare at “The End Times” and find themselves lured into a heist, just as the working port is about to make the inevitable transition to “prime seaside real estate.”

Curly Dean (James Burrows) heads our colorful cast of characters, goateed and tattooed, narrating from his trawler bunk, straight at the camera, telling us the place’s history and introducing his motley mates.

There’s pudgy, short-attention-span Budgie (Sam Glen), the former shipmate Codge (Michael Kinsey), whose drug abuse made him a liability no skipper would take on, and reliably discrete cabbie Weezy (Robbie Gee).

Jonas Armstrong is Charlie Graham, the fuming ex-fisherman who went to work for The Big Boss (Colm Meaney, of course) who contracts the fleet of boats and owns the fishpacking plants, where Queenie (Grace Long) and Demi, aka “Pitbull” (Melissa Batchelor) make an honest wage.

Graham is the one who realizes what Barr the Big Boss is about to do, sell out to Devine Residential Group, which will turn the “greatest fishing docks in the world” into flats, condos and Starbucks. Gilly (Lauren Foster), Curly Dean’s girl-in-port, also knows, but isn’t letting on. Graham is the one who pitches the caper.

“Fishermen we are,” Codge grouses. “‘Oceans F—–g FOUR’ we definitely are NOT!”

Nevertheless, a scheme involving Budgie’s mum (Catherine Adams), who is Barr’s paramour, and a safe full of cash destined for the crypto market is casually cooked up as the trawlermen finish up their latest booze and big-spending binge as “Three Day Millionaires,” the trawler crew ethos that most of what you earn had better be spent before taking on that next voyage, because it’s “bad luck” not to.

This is a good-natured action comedy that could seriously do with a bit of subtitling. It’s not like anyone outside of Limeyland is going to pick up on the thick, salty slang without it.

Stephenson’s script is fine at capturing the flavor of the place, where every fisherman, from the youngest to codgers like Curly Dean’s alcoholic Dad “Teapot” believes “It’ll come back,” that the decades-long downturn in fishing work is “just a lull.”

But a city’s slow death is a lot harder to instill desperation into than a story with more imminent peril. The stakes seem low, the caper under-planned and a lot less inventive than you’d like. Realistic? Sure. Kind of.

“This is nothing compared to the risks we take at sea!”

Maybe it was too expensive to show us that risk, as the boat scenes seem filmed in a painted up, docked and long-unused trawler rather than something we see in the “wine dark sea.”

The overlong opening act takes pains to give a Ritchie-esque freeze-frame introduction to every character, and suggests the women who love these seafaring men will have agency and a role in the caper. But they’re barely in this.

For Anglophiles like me, a “Three Day Millionaire” is always going to be worth a look, especially on a streaming platform that subtitles. But as even Guy Ritchie isn’t really making “Guy Ritchie movies” any more — God help us, “Aladdin 2” is on the way, and “Operation Fortune: Ruse de guerre” is finally getting a U.S. release in March — maybe mimicking the master, even somewhat clumsily, isn’t the smartest play these days.

Rating: unrated, moderate violence, drug abuse, sexual situations, profanity

Cast: James Burrows, Michael Kinsey, Sam Glen, Robbie Gee, Lauren Foster, Jonas Armstrong, Melissa Batchelor, Grace Long, Catherine Adams and Colm Meaney

Credits: Directed by Jack Spring, scripted by Paul Stephenson. An Entertainment Squad release.

Running time: 1:35