Where to Beacon Hill’s Grotto, an underground cavern of rich crimsons and twinkling chandeliers.

What for A massive feast modeled after the movie “Big Night,’’ in which two brothers attempt to revive an Italian restaurant with a dazzlingly ambitious meal. This is the 25th time Grotto has staged the event.

The scene Guests are encouraged to dress in 1950s attire. Slinky men in flashy suits, some with cufflinks and neon hankies, swirl wine. Another patron greets guests at his table like he’s welcoming them to his own personal Las Vegas. “Sit! Drink! Relax! Enjoy!’’ he cries. Owner Scott Herritt holds court in a plaid suit, while tuxedo-clad waiters maneuver the tiny dining room toting platters of risotto and antipasti. A Stanley Tucci lookalike charms a trim blonde in a dim corner; a troop of high school pals from Everett debate the merits of “sauce’’ versus “gravy.’’ It’s very loud here.

What you’re eating The menu for Grotto’s cultish feast is modeled after what the brothers served in the film. Family-style portions are epic. “We’re going to keep going with the food until you say stop!’’ Herritt cries. There are antipasti, three kinds of risotto (a vivid green pesto is the best), beef tenderloin, chicken Parmesan, salmon piccata, pan-roasted scallops, and whole-roasted pig. But such offerings appear paltry compared with Il Timpano — an individually plated, calzone-like bomb stuffed with pasta tubes and several meats, drenched in a sauce that tastes like liquefied, fennel-spiked pepperoni. Many infants are born smaller.

Care for a drink? Servers stroll the room with bottles of white and red, generously poured.

Overheard The satisfied shouts of bon vivants. “I run a supper club with people I’ve collected over the years,’’ announces a dapper fellow in pinstripes. “This consommé is definitely clarified,’’ notes an approving diner. “All I want is room-temp gefilte fish and a bourbon to go!’’ his pal cries. “If you call gravy ‘sauce,’ you won’t be allowed at my mother’s house,’’ a guy admonishes his seatmate. Another chap gulps a glass of red and leans across the table. “You know what I did when my girlfriend wanted to get married? I broke up with her!’’ Cheers all around. “What can I say? I’m a peacock! I need to fly!’’ he says. Herritt strolls to the front of the room. “Pace yourselves! This is family-style!’’ he cries. “But Weight Watchers might not approve.’’ Everyone applauds.

37 Bowdoin St., Boston, 617-227-3434, www.grottorestaurant.com

Kara Baskin can be reached at kcbaskin@gmail.com. Follow her on Twitter @kcbaskin.