The Viral Factor is a 2012 action film directed by Dante Lam and starring Jay Chou and Nicholas Tse. The supporting cast includes Lin Peng, Michelle Bai, Andy On, Carl Ng, Liu Kai-chi and Elaine Jin, with action choreographed by Dante Lam and Chin Kar-lok. A Hong Kong-Chinese co-production, the film was filmed from March 2011 to July 2011, and was theatrically released on January 17, 2012.