Louis Koo Tin-lok (Chinese: 古天樂; born 21 October 1970) is a Hong Kong actor and film producer. He gained popularity with his roles in television series The Condor Heroes 95 (1995), Detective Investigation Files IV (1999), and A Step into the Past (2001).
After 2001, Koo shifted his focus to films, frequently collaborating with director Johnnie To in films such as Throw Down (2004), Election 2 (2006), Romancing in Thin Air (2012), and Drug War (2012). His other notable films include Protégé (2007), Run Papa Run (2008), Connected (2008), Overheard (2009), The White Storm (2013), Paradox (2017), A Witness Out of the Blue (2019), and Twilight of the Warriors: Walled In (2024). For his performance in Paradox, Koo won the Hong Kong Film Award for Best Actor and Asian Film Award for Best Actor.
Koo Tin-lok was born in Hong Kong on 21 October 1970, and educated there. His father was an actor who later became a businessman. Koo is an alumnus of St. Teresa's School Kowloon, Carmel Secondary School and Carmel Divine Grace Foundation Secondary School.
Koo, along with his friends, were convicted by the court because of robbing in November 1990. Koo was sentenced to 22 months in the Correctional Services Lai King Training Centre. He neither mentioned nor acknowledged the event to the public after joining the entertainment industry, only after being exposed by the media in 1994.
During 1992 to 1993, Koo was a modelling agent, sometimes he worked as a model for advertisements and karaoke videos.
In 1993, Koo signed as a contract artist with TVB (Television Broadcasts Limited).
Koo started gaining wide recognition in 1995 with his leading role in a costume drama The Condor Heroes 95, a popular series based on a classic wuxia novel. In 1997, Koo began sporting an extreme tan (for which he is well known), which apparently enabled him to take on more contemporary roles. In 1999, Koo received TVB's Most Popular Actor Award for Detective Investigation Files IV. In 2000, Koo received TVB's Most Favorite Character Award for At the Threshold of an Era II. Koo took a different approach to his role in A Step Into the Past. This deviation from his usual cool aloof on-screen persona to a funnier, carefree and down-to-earth one resonated with the audience and widened his acting range. In 2001, Koo was given TVB's Most Popular Actor Award and Favorite Character Award Award once again for A Step into the Past. He then went on an indefinite hiatus from television and has since focused on his film career.
Due to the popularity of TVB dramas in the late 1990s, Koo amassed a sizeable fan base in Hong Kong, Taiwan, mainland China and South-east Asia.
Since 1994, Koo began taking on roles in films, such as the paranormal Troublesome Night series and many action films including Wilson Yip's Bullets Over Summer (1999). Koo acted as a mute boy living on rural island in romantic literary film Sealed with a Kiss (1998).
During 2001 to 2004, Koo signed contract with China Star Entertainment Group and starred in many romantic comedies, such as La Brassiere and Naked Ambition.
In 2004, Koo took on the role of Sze-to Bo, a perpetually drunk and despondent former judo champion with hereditary eye disease, in Johnnie To's Throw Down which was premiered at the 61st Venice International Film Festival. The movie was a marked departure from his usual commercial genres, and he also began his long-term collaboration with To and Milkyway Image.
Koo later received international acclaim for his chilling performance in Johnnie To's Election 2 (a.k.a. Triad Election), which was screened at the "Out of Competition" section at the 59th Cannes Film Festival (Election was competitive film at the 58th Cannes Film Festival). He won the award for Most Beloved Actor in the Hong Kong UA Film Awards 2006 through public voting for his role in Election 2.
In a female perspective romantic film Happy Birthday (2006) adapted by Sylvia Chang from Rene Liu's novella, Koo portrayed a sensitive man who continued to take care of his ex-girlfriend after his death.
Koo also took supporting roles in action movies, such as Jackie Chan's Robin B Hood (2006), Donnie Yen's Flash Point (2007).
His character as an unscrupulous drug addict in Derek Yee's Protégé (2007) differed from his previous performances, as he forwent his suave image for an emaciated look. The supporting role earned him positive critical feedback and Best Supporting Actor nominations at the Hong Kong Film Awards and the Golden Horse Awards.
In Sylvia Chang's female perspective gangster film Run Papa Run (2008), Koo played a reckless triad leader who tried to shield his daughter from his past misdemeanours. Koo earned Best Actor nominations in the Hong Kong Film Awards and Golden Horse Award for this role, which required him to portray a character from his late teens to his fifties. Since then Koo took more challenging father roles and middle-aged roles.
In the remake of Cellular, Connected (2008) directed by Benny Chan, he played an average Joe cast in a race against time to save a stranger.
In Soi Cheang's Accident (2009) which was a competitive film at the 66th Venice International Film Festival, Koo acted as a highly-strung killer-group leader who was good at disguising murders as accidents.