One of the most disarming things about "Happy-Go-Lucky" is how damned normal it is.

Its central character, a London grade-school teacher who goes by the nickname Poppy, is utterly without guile or malice. Played by Sally Hawkins ("Cassandra's Dream," "The Painted Veil"), this 30-year-old single woman isn't nursing deep psychological wounds or agonizing through bouts of loneliness and depression. She likes to knock back a few with her mates at the local pub, but there are no dark insinuations of self-medication.

Rather, Poppy just wants to have a good time. She enjoys people, even if they don't always enjoy her back, and she genuinely enjoys her life.

Her unvarnished cheerfulness makes the film a bit revolutionary in its own modest way. Writer-director Mike Leigh, whose credits include 1996's "Secrets & Lies" and 2004's "Vera Drake," is not one to shy away from angst, but "Happy-Go-Lucky" has the gumption to present compassion, kindness and good cheer as traits that aren't emblematic of anything beyond what they appear to be: decency.

The shuffling comedy-drama hinges on the most threadbare of story lines, but it is characterization here, not plot, that propels things along. Leigh is known for leading his cast through many weeks of rehearsals prior to shooting, and "Happy-Go-Lucky" appears to have been no exception. It has a relaxed, improvisational feel, stringing together a number of episodes that reveal Poppy's worldview and that of the world she inhabits.

STOLEN BICYCLE
The plot, such as it is, is triggered in the opening minutes, when Poppy's bicycle is stolen while she browses a bookstore. The theft prompts her to sign up for Saturday-afternoon driving lessons. Her instructor, Scott (Eddie Marsan, "Hancock," "The Illusionist"), is the antithesis of Poppy; he is a glowering, tightly wound misanthrope whose blackened disposition is rivaled only by his blackened teeth. The exchanges between the two are masterful blends of comedy and unease "” Scott's rants veer from funny to twisted "” that lend the movie a semblance of structure.

When not sparring with Scott, Poppy flits through a series of small adventures. She takes flamenco lessons, sees a chiropractor, visits her pregnant sister, counsels a young bully in her class and goes nightclubbing with her roommate and best friend, Zoe (newcomer Alexis Zegerman). In these scenes, Poppy's openness and congenial disposition are contrasted to the guardedness around her. Only rarely, as in her confrontation with a mentally ill homeless man, does the setup feel contrived.

With its loosey-goosey narrative and pace, the film places a sizable burden on its players. And they deliver. Marsan, a dependable character actor, displays raw intensity and great comic timing. As for Hawkins, Leigh wrote the part of Poppy for her, and she is stunning in it.

Her performance keeps Poppy from spiraling into caricature. She is charming and annoying, sometimes both at once. Audiences are likely to find themselves smitten by her, even when they can also understand why some characters find Poppy more than grating. That curious tension helps give "Happy-Go-Lucky" its forward momentum. For a movie in which nothing much really happens, it percolates with uncertainty.

"”Phil Bacharach