By Tuesday, August 25, Susan and Pierre Guérin, owners of the Sweet LifeCafé, had pretty much given up hope that the President would make a return visit to their Oak Bluffs eatery. President and Mrs. Obama had come for a meal in 2007 during the presidential campaign, sharing a quiet dinner on the breezy restaurant sunporch. The then-sena tor and his wife posed for a photo with theGuérins, which is now framed along with a note of gratitude scrawled on Sweet Life stationary by Mr. Obama. When the President announced his plans to vacation on the Vineyard, theGuérins hoped he would be tempted to return.

“[By Tuesday], we thought probably not,” said Mr. Guérin in an interview at the Sweet Life Wednesday morning. Rumors circulated that a presidential restaurant visit would warrant a full staff background check by the Secret Service, and an advance inspection of the property. TheGuérins at least expected to be notified ahead of time if the President planned to dine at their establishment.

Then, at 7 p.m. Tuesday night, United States Secret Service agents arrived at the restaurant to tell Mrs. Guérin that she had 30 minutes to prepare her staff to welcome the President of the United States. “That’s when [my wife] called me saying ‘You better come,’” said Mr. Guérin. “What happened is, they made a reservation under a different name.”

Secret Service agents quickly secured the building, blocked off Circuit avenue, and took their positions in and outside of the restaurant. “They don’t tell people to leave the restaurant. They don’t stop your business,” said Mr. Guérin. Instead, the agents asked for copies of the reservation list. Everyone inside the restaurant was allowed to stay, and any incoming guests would have to be verified on the list.

“They were the nicest people,” he said of the agents. “I’ve heard horror stories of the Secret Service taking over the place, but not at all. We were still in charge of our business.” Mr. Guérin said he expected the stern and formidable figures from the movies. “I don’t know if it’s the new generation of Secret Service, or it’s Obama’s policy to have those people trying not to disturb,” he said.

The party of seven, which included Mr. Obama’s advisor Valerie Jarrett and his sister Maya Soetoro-Ng, arrived at 7:30 p.m. A video clip of his arrival has since been posted on YouTube, showing the President carrying a baby, presumed to be his young nephew, as he approached Mrs. Guérin, who stood outside of the restaurant to greet the entourage. First Lady Michelle Obama followed closely behind in a crisp white sundress.

“He came here and they sat right away at the back,” said Mr. Guérin. The owner arrived at the restaurant shortly thereafter with his children and his mother, who was visiting from France, Mr.Guérin’s native country. He brought his family in to meet Mr. and Mrs. Obama. “I couldn’t let him go without having my kids see him,” said Mr. Guérin, smiling. “That’s when I got selfish a little bit.”

He continued: “They are charming, both of them . . .They’ve got great presence [and] charisma. Michelle was absolutely gorgeous . . .just down to earth.” Mrs. Obama introduced herself to the Guérin children, commenting that she wished her own daughters were there because they were quite close in age. She then spoke a few words in French to Colette Richin, Mr.Guérin’s mother. “Even Obama I think said ‘merci’ in French or a few things like that. It’s just so respectful to who I am, and just shows some culture,” said Mr. Guérin, obviously impressed that the Obamas took the extra effort. “It doesn’t cost. Everybody is capable of doing a few things like that. I don’t think every President would have thought of that.”

The Guérins then left the presidential party alone to enjoy their dinner. The party dined in a small private room, with a table of Secret Service agents just outside the door. The rest of the adjacent room was filled with regular patrons, with slight adjustments made to the table setup for security purpo ses.

“We didn’t really have time to realize what was happening as much as you would think we did,” said Mr. Guérin. “You’re running a business whether he’s here or not . . .[and] we had a full restaurant.” Some complications arose with the arrival of the VIP party, but customers were so happy to be dining with the President that they were unusually flexible. “We need an Obama night every night,” joked Mr. Guérin. “Having somebody like that, everybody was so happy that if you do make a mistake, nobody complains.”

The Secret Service monitored Sweet Life chef Scott Ehrlich and the rest of the kitchen staff as they prepared the President’s meal, which consisted of an appetizer of yellowfin tuna tartare, and an entrée of ribs and tenderloin steak. The First Lady opted for the Island greens and lettuces salad as a starter, and thesautéed halibut for her main course. The Obamas skipped the wine list in favor of cocktails, and Mrs. Obama chose a cosmopolitan.

The President emerged from the private dining room several times during his visit, always shaking hands with excited diners as he passed. The party left the restaurant to the same commotion to which they’d arrived, with people lining the street to catch a glimpse of Mr. Obama.

“After Obama left, that’s when we had Champagne, [and] I thanked everybody,” said Mr. Guérin. “The wait staff is so professional that they just keep going, keep moving . . .The only thing that is one of my regrets [was] not to have been able to do a staff photo with everybody with Obama . . .As soon as he left that room, the Secret Service were all over to control the crowd.”

Mr. Guérin could not say for certain whether or not the visit has affected business. “The few days after we have been completely booked,” he said. “The problem is, I don’t know if it is the Obama effect, because at that time of the year we are really super, super busy.

“We did get some reservations of people that wanted to sit at Obama’s table,” he said. But the weather last weekend had a negative impact on business, forcing the Sweet Life to close its outdoor patio due to the rain. “For us, that’s a big part of our business. Obviously if there wasn’t that tropical storm, we would have done a weekend that was completely crazy.”

Business boost or not, Mr. Guérin was grateful for the chance to welcome the President once again. “Not only am I proud that he came here, but I’m proud that we were the only restaurant he went to,” he said. “I would say one thing that differentiates us from all the nice restaurants in Edgartown, for instance, is the fact that we have the most mixed crowd . . .and we are proud of that . . .He had a good time, good food. He had good privacy, which I think is very important. Not every restaurant offers privacy like we do.”

He continued, describing the winding down of the summer season: “The whole staff has been doing hard work to go through the summer, and now [we are] all tired. It’s the moment when it’s becoming a little tough because it’s the end of the season. Everybody is kind of shaky. And it was a great boost of morale, a great boost of everybody’s self-esteem to say, ‘Hey, Obama chose our restaurant because he liked the place.’

“Somebody at least noticed, the hard work we put in the restaurant pays off,” Mr. Guérin smiled.