“Equalizer 2” is the kind of raise-the-bar sequel that can convert a franchise skeptic into a fan.

Denzel Washington had a bad first turn as aged avenger Robert McCall in 2014’s “The Equalizer.” It felt like a faded 1980s action film full of embarrassing false notes. McCall, a mild-mannered old hand, worked at a Boston home improvement superstore and ran a side business as a freelance vigilante. The finale was an in-store massacre with McCall using construction tools to turn Russian gangster/pimps into a gooey mess. It was equal parts “The Punisher” and “Home Alone” ineffectively staged and painfully dumb.

If you forget that movie — which shouldn’t be difficult — and approach this as a stand-alone rather than a sequel, it’s pretty snazzy. It can’t quite keep its mind on telling a story, but it’s grounded, features a good villain and has a mix of tense suspense and kinetic bloodshed that is enjoyably nasty. This is all the more surprising seeing as how, like the first movie, it is directed by Antoine Fuqua and written by Richard Wenk.

It’s easy to see why Washington would make this his first sequel. McCall is a quiet, keep-to-yourself workingman, but it’s suggested that he once was the king of Black Ops. That signature Washington expression where he looks at some unlucky sap with cold eyes and smiles like a shark comes into play very effectively. And when trouble arrives, he can pound his enemies like a blacksmith. What created his hard side is more implied than explicitly detailed, and that makes us watch Washington eagerly, searching for clues.

McCall is now a Lyft driver, so he gets to tool around Boston crossing paths with trouble rather than waiting for it to come find him. In his spare time, he’s a neck-snapping guardian angel, appearing where youngsters are in danger, beginning with a brutal, Bond-esque showdown against kidnappers.

The CIA experience that the first film hinted at is expanded here as colleague Susan Plummer (Melissa Leo) and her husband Brian (Bill Pullman) reappear to offer friendly support. In a stroke of excellent casting, the film also brings in a younger teammate in “Game of Thrones” heartthrob Pedro Pascal, who owns almost every scene he’s in.

There are still areas that need to be sanded and repainted. McCall has the ability to see slow-motion outcomes of approaching fights, and the predictive mumbo-jumbo is grating. There’s also an extended side story about McCall’s involvement with an artistic teen who’s being recruited by a drug gang, an added level of hokum on a lean, mean story.

Still, following the first film, this feels like a solid triple after a swing and a miss. This time the guilty party isn’t obvious from the outset, the gumbo of red herrings we are served is quite tasty and the inevitable final showdown is remarkably well-crafted and menacing. I haven’t seen anything like it before, and I have seen a lot.