Putting the punch in punchline

“Are you going to let me in?”

That’swhat Florence (Greta Gerwig) murmurs as she navigates the traffic on a busy LosAngeles street. She might ask the same question of the title character in“Greenberg,” writer-director Noah Baumbach’s acidic comedy, in which BenStiller plays a stubborn slacker who spends his days fashioning personalcrusades out of minor inconveniences and wallowing in nostalgia, although it’shard to imagine his supposed glory days were anymore glorious than hisseemingly pointless present-day situation.

Greenberg— first name Roger — makes a habit of keeping the world and everyone in it atarm’s length, although he’s not too proud to accept an invitation from hiswell-heeled brother, Phillip (Chris Messina), to stay at Phillip’s Los Angelesmansion while Phillip and his family vacation in Vietnam. “He’s delicate,”Phillip says of Roger, a rather kind way to describe someone whose grocery listbegins with whiskey and ice cream sandwiches and doesn’t go much further.

“LeonardMaltin would give me, like, two and a half stars,” Roger tells his formergirlfriend, Beth (Jennifer Jason Leigh, who co-wrote the screenplay withBaumbach).

Florence is Phillip’s personalassistant, a woman who understands every aspect of neediness. At a party, shereaches out to a potential partner by telling him, “I’ve been out of college aslong as I’ve been in, and nobody cares if I get up in the morning.” Now there’sa pick-up line you don’t hear every day.

Eversince his debut film “Kicking and Screaming” 15 years ago, Baumbach hasspecialized in telling stories about privileged, jaded, often intellectualcharacters who can’t seem to get their acts together. In “The Squid and theWhale,” writers Jeff Daniels and Laura Linney are both brilliant when it comes toputting words down on paper and utterly clueless when it’s time to talk totheir kids, or to each other. Nicole Kidman’s character in “Margot at theWedding” is a narcissistic, never-satisfied author whose only joy comes frommaking everyone around her miserable.

These are not particularly easycharacters to warm up to, and neither is Roger, who initially seizes uponFlorence’s low self-esteem and uses it as a weapon against her. When Florencefinds herself in the midst of a major crisis and must call on Roger for help,he responds in shocking, mocking ways. He doesn’t treat his friend and formerbandmate, Ivan (Rhys Ifans), much better.

“I’m not one of those preening L.A.people who wants everything to be all about them,” Roger tells Florence, astatement that’s only half-true: Roger comes from the East Coast.

Stiller is terrific here, investinghimself in a character in a way he hasn’t done since his enormously underratedwork in “Permanent Midnight” and “Your Friends and Neighbors” more than adecade ago. But the true revelation of “Greenberg” is Gerwig, who pulls off theastonishing trick of making Florence endearing and touching instead of purelypathetic. While Roger may treat her as a punching bag, Gerwig gives Florence abackbone of solid steel; it may be buried, but it’s definitely there. That coreof strength and resilience turns a victim into a victor, and makes Florencefascinating.

In a time when many comedies panderto their audiences by offering up comforting clichés and lowbrow jokes, “Greenberg”boldly goes in exactly the opposite direction. Baumbach and Jason Leigh knowhow to put the punch in punchlines, and many of the film’s funniest moments arealso the most disturbing.

While they take a certain delightin exposing Roger’s pettiness — he writes a complaint letter to AmericanAirlines not about delays or poor service, but about the low quality of thebuttons on the recliner seats — and Florence’s all-consuming desire to beaccepted, the writers also dare us to look beyond Roger and Florence’s flaws tosee what lies beneath. Roger habitually coats his lips with cherry ChapStik;Florence frequently picks at or pinches her lips.

Obviously, they must be made foreach other, right?

 Greenberg showtimes