Few actors are employed to draw a crowd since the reinvention of blockbuster filmmaking, which promotes the concept or the characters way above the people playing them. However, there remains a handful of actors who can still draw a crowd. Actors whose presence tells us, this is a movie worth taking a look at.

Sam Rockwell is one of those actors. Someone who consistently chooses interesting, low-to-mid budget movies. From Moon to The Way, Way Back to Three Billboards, Rockwell’s choices seem to align with what many of us want to see.

Sadly, even Rockwell is capable of a duff choice. Even still, to discover he’s involved with a movie like Blue Iguana is still a hell of a surprise.

Eddie (Rockwell) is working in a diner. A parolee trying to keep his nose clean along with his best mate Paul (Ben Schwartz). The pair are approached by nerdy lawyer Katherine (Phoebe Fox) to take part in a small heist in England, and are soon whisked off to London to steal a bag.

Inevitably, the job goes awry. Sort of. Well it does and it doesn’t. It’s not entirely clear, like much of the plot that follows. It’s the kind of comedy heist plot that has every cliche and idea thrown at the wall and then included in the final cut.

Holed up in a dingy warehouse watching a pub full of villains, Eddie, Paul, Katherine and their small crew of forgettable sidekicks set about doing some heisty stuff, interspersed with laugh-free comedic sequences (even Rockwell can’t make a cliched exchange over Cockney rhyming slang funny) – and the occasional joke that lands for a total of around three to four in the 95 minute running time.

Elsewhere there’s a Begbie-lite turn from Paul Ferdinando, that’s as interesting as it is irritating, a bizarre turn from Amanda Donohoe and a couple of scenes that no doubt paid for Simon Callow to have a nice holiday somewhere.

Rockwell is, by some distance, the best thing in this. It’s just hard to fathom how he got involved. Tonally it’s all over the place, there’s next to nothing driving the plot forward (the titular diamond is only mentioned halfway through, and looks like the prop was designed by Gerald Ratner) and most of the cast are having way more fun than the audience.

Rockwell may draw some to watch this mess, but he’ll end up regretting that.