A career retrospective on Alec Guinness runs at the Museum of Fine Arts Boston this week, starting with the Ealing Comedy The Lavender Hill Mob. There are a lot of actors and actresses today who get credit for switching between drama and comedy, and it seems there are more and more dark-and-gritty roles being taken by comedians these days (see: Jonah Hill, Chris Pratt, Jesse Eisenberg, Adam Sandler). It’s worked the other way, too, which is why Tom Cruise shows up in Tropic Thunder and ends up being the best part.

Guinness was something else. This isn’t a dramatic actor trying comedy any more than his role in Bridge on the River Kwai is a comedic actor attempting drama — it’s just Alec Guinness, for lack of a more detailed explanation, completely at home in both arenas. Granted The Lavender Hill Mob isn’t a laughfest of super-zany proportions (Guinness nailed those too, though, with Kind Hearts and Coronets and The Ladykillers), but it’s a far cry from Kwai.

We meet the mild Mr. Holland as he dines at an upscale restaurant in Rio de Janeiro with another Englishman who is clearly new in town. Holland seems to be showing him the ropes, gladhanding everyone who passes by the table and tipping generously the waitstaff and maître d’. He talks grandly of the last year of his life. And then we see how that year began: Holland is a miserable employee of a London bank, supervising the pouring and delivery of gold bullion across the city. When he meets Mr. Pendlebury, a manufacturer of souvenir Eiffel Towers, the pair hatch a plan to rob the Bank of England by melting the bullion down into the Eiffel molds.

The Lavender Hill Mob is never riotously hilarious, but the smile Guinness and Co. put on your face is a lasting one. Holland and Pendlebury recruit the rest of their mob by going to saloons and racetracks, sitting a few seats apart, and screaming to each other about how the lock on the safe in Pendlebury’s office is broken and how much money is unprotected in the safe and what was the address again? Later, they accidentally sell the solid gold Eiffels to a group of schoolgirls atop the actual Eiffel Tower, and the following sequence of Holland and Pendlebury careening down the entire spiral staircase in an effort to beat the elevator is the most gleeful in the film. “This isn’t funny,” Holland yells and they grip the sidewall and hurtle around and around. Halfway down the pair can’t stop laughing, and when they finally hit the bottom stair they can’t stop spinning around.

Charles Crichton directed Mob, and though his career is slightly inconsistent he also directed A Fish Called Wanda before his death. That’s probably the film in his oeuvre that most resembles Mob: the script is funny, sure, but never downright hysterical — it’s the actors who make it so memorable. Stanley Holloway deserves mention as Mr. Pendlebury, and he and Guinness play perfectly off each other. Immediately following their heist, the inflated pair get drunk in the apartment building and decide to forthwith call each other “Al” and “Dutch”. They’re “real” gangsters now.

And never for a moment does it occur that this is Colonel Nicholson. This is Prince Feisal. This is Obi-Wan Kenobi rolling around in the dirt so it looks like he’s put up a struggle against the phantom bank robbers. Actors like Guinness are rare these days, if they’re around at all, and so a retrospective on a career as varied and dynamic as this is not to be missed. It’s fitting to start with The Lavender Hill Mob, too. There’s a lot to like, from Crichton’s direction to T.E.B. Clarke’s Oscar-winning script to the general air of Ealing Comedy. The great Douglas Slocombe (famous cinematographer of such greats as Raiders of the Lost Ark) shows some of his early chops here as well. But it’s Guinness, rightfully, who’s front and center in one of his more overlooked roles. This is Alec Guinness at his best — and not just his comic best.