Chief Executive Carrie Lam Cheng Yuet-ngor encouraged Hong Kong's young people on Sunday to learn and gain strength from their predecessors who devoted themselves to fighting for the nation a century ago.

Lam conveyed her expectations at the Hong Kong premiere of the movie 1921.

The movie, which celebrates the 100th anniversary of the founding of the Communist Party of China, is mainly about how a group of Chinese youth from all over the country successfully held the first congress of the CPC in Shanghai, after being suppressed and closely watched by various foreign powers.

Since its premiere on the Chinese mainland, the movie has raked in a box office of 3 billion yuan ($464 million) in just four days.

At the event, Lam said the Hong Kong Special Administrative Region has always been part of the country, and the history of the past 100 years has demonstrated the Party's faith in safeguarding national sovereignty and territorial integrity, as well as its caring about the well-being of Hong Kong people.

Lam said she hopes the film and creative industries in both the mainland and the HKSAR can bring more educational and positive art works to the community, telling good stories of the nation and the city to the world.

Leung Chun-ying, a former Hong Kong chief executive and currently a vice chairman of the National Committee of the Chinese People's Political Consultative Conference, also praised the film in a social media post, saying that the movie helps fill the knowledge gap of many Hong Kong people regarding the country's history from 1921 to 1949, the period leading to the founding of the nation.