Hundreds of South Koreans plan to march on Saturday in Seoul against President Park Geun-hye, whose increasingly harsh treatment of union members and dissidents has led to criticism comparing her with her late father, Park Chung-hee.
The rally will be the latest in a series of mass protests against the government in recent months, although police believe the turnout will be smaller than huge demonstrations earlier this month and on Nov 14, when dozens were injured in a clash between police and protesters.
Although Park still has a strong base of loyal supporters, dissatisfaction has been growing. Demonstrators criticize her conservative policies in labor, trade and education and also what they see as her attacks on personal and political freedoms.
There is also widespread frustration among young people over joblessness and inequality, analysts say, which has inspired an Internet buzzword, "Hell Joseon", referring to the feudal Joseon kingdom that ruled Korea before it was colonized by Japan in the early 20th century.
Government figures show that the unemployment rate for people under 30 is approaching levels not seen since the late 1990s, when millions lost their jobs during a crippling financial crisis.
The demonstrations have grown because protesters believe their causes have been neglected by politicians and the media, said Chung Jaewon, a social science professor at Seoul's Kookmin University.
Park's government has responded by clamping down on the labor and civic organizations involved in organizing the protests.
Prosecutors are also considering indicting an arrested labor union official for sedition, a crime punishable by up to 10 years in prison, over the eruption of violence at the November rally. South Korean courts have not convicted a defendant of sedition since 1986, when dictator Chun Doo-hwan was in power, legal experts say.
Police have also vowed tougher actions against protesters who use violence. Critics, however, say the injury of a 69-year-old protester, who remains in a coma, and the heavy use of tear gas and water cannons mixed with pepper spray mean police put lives at risk last month by using unreasonable force to break up the demonstrators.
A follow-up rally on Dec 5 was peaceful as thousands of people marched toward the Seoul hospital where the man in a coma was being treated.