Catherine Ellsberg '16Staff Writer Were it cast differently, it would be tempting to dismiss Paul Weitz’s compact, 80-minute film “Grandma” as mere indie-drama fodder. Fortunately for everyone involved, Lily Tomlin plays the film’s title character, ripping into the film at full-throttle and veering from hilarity to quiet tragedy often within the same scene. It’s impossible to ignore Tomlin’s genius as a comedian or her game-changing role in the history of comedy; indeed, as film critic A.O. Scott reminds us, she stands in as a kind of “foremother” to such working greats as Tina Fey and Amy Poehler (and has recently received a resurgence of attention with the Netflix series “Grace and Frankie”). But in “Grandma,” what makes Tomlin, who plays matriarch Elle Reid with biting acerbity, so astonishing is that with each excruciatingly funny comeback, we get the sense that the zingers belie a deeper sadness – one that threatens to bubble to the surface at a moment’s notice. “Grandma” unfolds over the course of one day in the lives of Elle and her teenage granddaughter, Sage (Julia Garner), who is in desperate need of quick cash for an abortion scheduled that afternoon. Elle, who once was a famous poet rubbing elbows with Betty Friedan, has just that morning broken up with her girlfriend of four months, Olivia (the always marvelous Judy Greer). Already in a bad mood, she tells Sage that she has no money and proceeds to display her windchime made of cut-up credit cards. Bit by bit, we learn that Elle has recently lost her partner of 38 years, Violet, and for the rest of the film, it becomes clear that Elle’s no-nonsense veneer and snapping insults serve as a tough but cracking piece of armor. Telling Olivia that she was merely a “footnote” to her previous relationship, Elle terrifies the audience, but soon after she collapses in her shower sobbing. For all its weary bitterness and troubling material (the film leads up to an abortion, portraying the situation with gravity in a kind of antidote to the chipper 2007 film “Juno”), Lily Tomlin keeps the film rolling with uproarious, often wacky, humor. “Grandma” features a formidable supporting cast, including the aforementioned Judy Greer, as well as Laverne Cox, Marcia Gay Harden, Elizabeth Peña and Sam Elliott, all of whom add color while stepping aside to give Tomlin the last word. Though the film is standardly shot and paced, it does a superior job of capturing the rhythm and fabric of daily living, stressing the differences between the teenage Sage and the older Elle (self-described as “approaching 50”). Some of the funniest scenes highlight this generational gap, such as when Elle asks Sage’s sometimes creep of a boyfriend, “Why didn’t you use a condom? Or for humanity’s sake, get a vasectomy?” At another point, Elle stands dumbfounded when she realizes her granddaughter has never heard of “The Feminine Mystique” (“Mystique’s a character in “X-men,” mumbles Sage). At the end of the day, after trying to scrounge up the cash and paying a visit to Sage’s workaholic, perpetually-stressed mother—“I’ve been scared of your mother since she was five,” Elle admits—the film closes with a final shot of Elle. Walking home alone after a tough day, she recedes slowly from the frame while the camera lingers to watch; after a minute, we can just barely see Tomlin’s figure move a little, as if she were still having the last laugh.