Perhaps one has been too hasty when one has declared “Is there anything worse than Imitation Tarantino, than Guy Ritchie Lite?”

Because when wild card and now Oscar-winner Sam Rockwell’s involved, and Simon Callow and a bevy of screwy British character actors, all wrapped up in a cascading catastrophe of carnage-covered capers titled “Blue Iguana,” all bets –as we are given to say –are off.

Producer turned writer/director Hadi Hajaig (“Cleanskin”) gives away the game by having a character, the chatterbox ex-con Paul (Ben Schwartz of “Parks and Recreation”) dream of making “MY indie film. Do you like LENS FLARE?”

Hajaig doesn’t give us much of that, but he takes a shot at filling the screen with “the cool parts” — slo-mo shootouts, blood spray played for laughs, one-liners, Brit-vs-American slang and mob mores.

“Shambolic” is the perfect word for it, even if he does have one of his dopes wonder, “What’s shambolic?”

And if it gives you the creeping feeling that he’s some hack spending a lot of mummy’s money making himself a movie career, it’s still laugh-out-loud funny as often as not.

Eddie (Rockwell) and Paul (Schwartz) are ex-cons riding out parole in a New York chain restaurant/diner when in strolls England’s Plain Jane — aka Katherine, a British lawyer referred to them by a fellow hoodlum “English Tommy.”

She’s got a job for them In London. Travel arrangements, pay, parole? She’ll take care of it. Even though she’s frumpy, clumsy and seemingly out of her depth, the boys buy in.

Phoebe Fox (“Eye in the Sky”) plays Katherine with kind of posh-accent, dressed-down guile. She knows just which screws to turn because she’s not just a lawyer, she’s a barrister with an ear for illegality she can leverage in her favor.

She needs the Yanks to intercept this satchel that’s to be handed off in a natural history museum. They can be armed, but “no violence.” Naturally, with Paul a bit high-strung and Eddie plainly careless and/or rusty, much that can go wrong does.

That pursuit of the package leads to another heist, this one involving the “Blue Iguana” of the title. Katherine is mixed up with Mr  Big, with a name referencing an Orson Welles thriller (Peter Polycarpou), and he’s got Deacon (Peter Ferdinando of “Tommy’s Honour” and other films, hilarious here) as his “muscle.”

Deacon minds his mum’s pub, The Prince of Wales, loves double-crosses, his ’70s vintage mullet and denim jacket.

“They were me Dad’s.”

He hates Katherine and REALLY hates his mum. As she’s played as a braying, insulting, over-sexed harpy with a smoker’s laugh by Amanda Donahoe (a stitch), we can see where his “issues” come from.

“You stink of ketchup and…farts.”

The more complex the caper becomes, the more competent Eddie seems. Maybe he’s just trying to impress Katherine. Hard to tell. Lose the glasses, the shapeless sweaters, ’60s school teacher hair…anyway.

That rising list of plot complications is where Hajaig rather loses the plot. Fortunately, he’s got a lot of funny people on set riffing around some amusing twists.

Paul wonders just where one’s prostate is, and somehow takes a shine to Deacon’s mom, filling the pub with lies as he stakes her out.

“I work for NASA. It’s crazy, Stephen Hawking got me the job…Name’s Teddy Roosevelt.”

Eddie takes an interest in Cockney slang — “‘Throw a pint down my Gregory.’ What’s that mean?” Gregory Peck, and what rhymes with Peck? “Preh-ey good, innit?”

The shootouts in enclosed spaces create an awful mess, and a chance for Paul to try out his tampon-as-bullet-hole-plug theory.

And so on.

As the Americans, with the erudite and fey English Tommy (“We know what we are, but not what we would be.”) stake out the pub, they enlist Tommy’s thespian uncle (Callow, amusing) and his “old gang” — old actors who take notes in the bar and plummily recite the profane clues they overhear in Royal Shakespeare Company English.

Like lesser Ritchie and most Tarantino, there’s a lot of “just go with it” to “Blue Iguana.” There are built-in ’80s pop conceits that reward the viewer on the same wavelenth, “Private Idaho” era B-52s and the like.

Rockwell does this sort of ditzy cool as well as anybody, and as shocking as the violence is, it’s as funny and not as horrific as the stuff we saw him win the Oscar for in “Three Billboards Outside Ebbing, Missouri.”

“Blue Iguana” could fall on either side of the sliding “whatever” scale, probably more Netflixable than something to run out and see. But Rockwell, Schwartz, Fox, Ferdinando and Callow make it engaging in between its darkly-funny bursts of slow-motion violence — be their characters expertly menacing, or just mean and inept.

MPAA Rating: unrated, violence, profanity

Cast: Sam Rockwell, Phoebe Fox, Ben Schwartz, Peter Ferdinando, Amanda Donahoe, Al Weaver, Simon Callow,  Peter Polycarpou
Credits: Written and directed by  Hadi Hajaig. A — release.

Running time: 1:40