HONG KONG — On the eve of today’s Olympic torch relay through Hong Kong, officials allowed actress Mia Farrow into the Chinese territory so she could bash China’s cozy ties with Sudan, although they had earlier kicked out pro-Tibet activists.

It’s all part of Hong Kong’s delicate balancing act — pleasing political masters in Beijing, while trying to be a free society and a freewheeling global financial capital.

The relay through canyons of skyscrapers is a big challenge for Hong Kong’s leaders and police. The Olympic flame is finally back on Chinese soil, and Beijing doesn’t want a repeat of the protests and chaos that dogged it during a 20-nation overseas tour.

Residents were encouraged to wear red to show their support for the flame, and about 3,000 police will be on hand.

But Hong Kong is a place with civil liberties unrivaled in the rest of China. One university student has said she would unfurl a Tibetan flag, and a maverick lawmaker was expected to organize a human rights protest.

Although Beijing makes all the big political decisions, Hong Kong was promised a wide degree of autonomy under a formula called “one country, two systems.”

But for special events, Hong Kong leans more toward the “one country” part of the formula. In the past week, authorities used a blacklist to stop seven pro-Tibet and human rights activists at the airport. After questioning, they were deported.

Many thought that Ms. Farrow might be turned away at the airport when she arrived to give a speech critical of China’s ties with Sudan. After reaching the immigration desk to get her passport stamped, officials escorted her away to discuss her plans.

“They wanted some reassurance that we were not here to disrupt the torch relay, which of course we are not,” Ms. Farrow told reporters.

Ms. Farrow is scheduled to speak about Sudan at the Foreign Correspondents’ Club today.