A year and a half after Harvard forced Upstairs at the Pudding from the third floor of the Hasty Pudding building, the upscale restaurant emerged from its chrysalis Monday as Upstairs on the Square, in a building at the intersection of Winthrop and JFK streets.

Only the restaurant’s first floor will be open for dinner the rest of this week, but its fancier second floor will start serving on Saturday, coinciding with the Harvard-Yale football game. From then on, the restaurant will be open full time daily, from 11:30 a.m. to midnight.

Despite the fact that co-owners Mary-Catherine Deibel and Deborah Hughes did not publicize the restaurant’s opening, Deibel said that the restaurant has been well-attended so far.

“People have been coming in because it glows out from the street,” Deibel said of the Winthrop Square location, whose large windows look out onto the square.

Many former regulars came to check out the new Upstairs Tuesday night, but some said part of the old restaurant’s charm has been lost.

“It doesn’t possess all the Hasty Pudding stuff that was really kind of wonderful,” said Scott Dahill, speaking fondly of the Theatricals programs and memorabilia dating from the 1840s on the walls of the old restaurant location.

After the University took over the Hasty Pudding building from the insolvent student group, they soon tried to force the restaurant out of the building it had occcupied for 20 years.

After a series of lawsuits with Harvard, the parties eventually settled on a compromise, allowing the restaurant to stay open in its old location through Commencement 2001.

Ironically, Upstairs’ new building originally housed the Pi Eta theatrical and social group, the Pudding’s now-defunct archrivals.

Others argue the former restaurant had gone stale, and the new location had a more vibrant image.

“It’s so much fresher and polished,” said Locke-ober bartender Carah M. McLaughlin.

“They have it going on,” she added.

The building, which housed the Market Theater for a little over a year, now looks like a Betsey Johnson boutique—leopard and zebra-print carpets line the floors, pinks and purples dominate an unusually bright color scheme, and whimsical chandeliers illuminate the room.

While planning for the reopening, Hughes, who is responsible for the interior design, said she tried to retain the Pudding’s trademark style while allowing the new restaurant to develop a distinct identity.

The first floor pays tribute to the restaurant’s Pudding past. The owners named it the Monday Club Bar in honor of the restaurant’s original investors, who used to come in on Mondays, when the Pudding was closed to the public. The room’s green, purple and pink color scheme also mimics that of the old restaurant.

The feel of the second floor, baptized the “Jewel Box Soirée Room,” is quite different.

It uses art nouveau and art déco designs, executed in gold leaf, pastels and bright red polka dots.

The “Jewel Box” refers to the bar at the far end of the room, whose heavy-handed gold leaf application is supposed to make it “shine like a jewel,” as Hughes puts it.

While Monday Club Bar will serve American dishes, the Soirée room, as the name implies, will be devoted to French cuisine.

Deibel and Hughes also replaced the restaurant’s old crocodile mascot with a zebra—“a horse with design gone wild,” according to Deibel.

The comparison makes sense, if the Market Theater—whose building was renovated to staid, somber splendor for $2 million by founder Gregory C. Carr—can be thought of as the horse.

Carr, meanwhile, is in the midst of building a new house from scratch for the Market Theater at the intersection of Mass. Ave. and Arrow Street. He originally sold the Upstairs on the Square property in order to expand the capacity of his 100-seat theater, but due to conflicts with city residents, the new theater will probably seat only about 150.

—Staff writer Eugenia B. Schraa can be reached at schraa@fas.harvard.edu.