The security breach happened Thursday night, only 15 minutes before Sochi’s Olympic Park played host to its initial event of the Winter Games. No one saw her slip in. Her identity was unknown, and she fit only the most general description: brown eyes, sandy hair, medium height.

All the considerable security surrounding these Olympic Games — and worldwide publicity about her fugitive pack — could not stop her from sizing up her mark and making her move. And no volunteers, police or Cossacks tried to capture her when she plopped down on the ground, wagged her tail and cadged bits of chicken kebab from a table of twentysomething Russians. On the eve of the Opening Ceremony of the Sochi Games, the controversy over stray dogs — and related worries about toothpaste bombs, terrorist infiltration, hostility to gays and unfinished hotel rooms — finally ceded some of the spotlight to the athletes.

Though the Olympics officially begin Friday, 12 new medal events forced these overstuffed Games into an early start. The Caucasus Mountains, part of the territory inhabited by separatist insurgents, became a playground Thursday for men’s and women’s slopestyle snowboarders and women’s moguls skiers. Home-country hero Evgeni Plushenko put on a dazzling show at the Iceberg Skating Palace on the opening night of team figure skating.

The troubles did not disappear entirely. The heavy security presence was reflected in the military boats that plied the waters of the Black Sea, just off the coast near the Olympic Village, and in the excited barking of police dogs at an Olympic Park vehicle checkpoint. A tangle of razor wire lay just outside the fenced perimeter — the Ring of Wire inside the Ring of Steel — near the hockey arenas.

Russia’s deputy prime minister, Dmitry Kozak, said Thursday, “We can guarantee safety and security in Sochi.” U.S. women’s hockey player Gigi Marvin, a former Gopher from Warroad, Minn., was among several athletes to say she was not thinking about the multiple controversies at all.

“Our excitement level is through the roof, to the moon,” Marvin said after practice at Shayba Arena, where the Americans open the women’s tournament Saturday against Finland. “We’re ready. Let’s get going.”

The Sochi organizing committee has kept the details of the Opening Ceremony as closely guarded as a state secret. It has been running tests of its pyrotechnics, setting off nightly explosions that generate anticipation rather than apprehension.

Marvin and her teammates were planning a vote to decide whether they would march in the ceremony or watch from their village rooms so they could rest up for Saturday’s game. If they go, they will be among athletes from a record 88 nations, including first-time Winter Games participants Togo, Timor-Leste, Tonga and Zimbabwe.

Putin, Russia front and center

The ceremony will feature plenty of Russian pop stars and TV personalities, with President Vladimir Putin front and center. Putin, who campaigned heavily to bring Russia its first Winter Games, is also eager for the Games to begin. Though he expected the country’s $51 billion investment to burnish Russia’s image abroad, he now hopes the spectacle can reverse the tide of negative publicity unleashed by allegations of human-rights violations, corruption, environmental degradation and the killing of stray dogs roaming freely around the city.

Putin went on a charm offensive Wednesday, stopping to talk with five U.S. women’s hockey players — including former Gopher Megan Bozek and current Gopher Amanda Kessel — while visiting the Olympic Village. But the political flash points flared again Thursday, when United Nations Secretary-General Ban Ki-moon addressed a meeting of the International Olympic Committee and urged people of all nations to reject discrimination against gays.

Thursday night in the Olympic Park, the three friends feeding the canine interloper wanted only to see the athletes. They had come from Volgograd, the city now known for three recent suicide bombings by the separatists, for two days. Asked whether they were upset that the dog had come into the park, one of them, a young woman named Karina, laughed and gave it another piece of her dinner.

The dog got what it wanted, and so did they. Inside the Iceberg arena, Plushenko gave his countrymen a fine start, lifting it to the top of the team figure skating standings with a second-place finish in the men’s short program. But like everything else about these Olympics, it wasn’t easy.

“I am happy with everything,” he said. “Believe me, it is so difficult skating an Olympics at home, because many people are here, waiting for something incredible.”