For those unfamiliar with Steven Mackintosh — a British actor with one of those wonderfully impassive, Everyman faces — he’s the revelation and best reason to watch “Inside Men,” a four-part BBC America heist drama, the details of which unspool in flashback. While the time-hopping device is hardly novel, the idea of each episode filling in more glimpses of the backstory does pull the viewer along and stoke tension, until we see how the intricate pieces ultimately fit together. If only everything in this limited series were as compelling as its unlikely leading man.

Mackintosh’s John is living a classic life of quiet desperation. He has a wife and adopted kid, while managing a cash-counting house with the sort of precision normally reserved for a Dickens character.

Yet when he realizes two subordinates, Marcus (Warren Brown) and Chris (Ashley Walters), are trying to sneak money out of the branch, his reaction comes as a bit of a surprise. Far from canning or incarcerating them, John summons the pair to his office and decides why not go after a major payday, working in concert with actual criminals to pilfer millions?

Of course, there are complications and considerable distrust — including the operation’s skeptical financier, nicely played by Irfan Hussain — as well as the matter of how the process affects each participant, along with the women in their lives. That includes Marcus’ girlfriend Gina (Kierston Wareing, one of three “Luther” alums reunited here, joining Mackintosh and Brown).

Mostly, though — in a manner thematically similar to “Breaking Bad” — there’s the great pleasure of seeing Mackintosh’s character evolve from milquetoast to mastermind, calm banker to calculating badass. Becoming a criminal clearly liberates him, in a variety of ways.

It’s such a bravura, tightly wound performance — played with restrained intensity by the kind of star seldom featured on American TV — as to keep one glued to the show right up until its slightly anticlimactic, disappointing payoff.

Written by Tony Basgallop and directed by James Kent, the four hours also prove distinctive for what they don’t do, eschewing big dramatic flourishes to methodically study the players. The main drawback is that compared with John’s storyline, the time spent on Marcus, wrestling with financial troubles, and Chris, about to become a father, feels unremarkable.

Balancing those factors, “Inside Men” finally feels uneven but still worthwhile, demonstrating a common challenge in TV and crime: No matter how well you draw things up on paper, it’s not always that easy to deliver a big payoff.

Inside Men

Limited series; BBC America, Wed. June 20, 10 p.m.

  • Production: Filmed in the U.K. by BBC Prods. Executive producer, Hilary Salmon; producer, Colin Wratten; director, James Kent; writer, Tony Basgallop;
  • Crew: camera, Tim Fleming; production designer, Anna Pritchard; editor, Paul Knight; music, Paul Englishby; casting, Andy Morgan. 60 MIN.
  • Cast: John - Steven Mackintosh <br> Marcus - Warren Brown <br> Chris - Ashley Walters<br> Kirsty - Nicola Walker<br> Gina - Kierston Wareing<br> With: Leila Mimmack, Irfan Hussain.<br>
  • Music By: