Lethal Weapon 4 is a 1998 American buddy cop martial arts action thriller film directed by Richard Donner, starring Mel Gibson, Danny Glover, Joe Pesci, Rene Russo, Chris Rock and Jet Li. It is the third sequel in the Lethal Weapon series of films. This was Jet Li's first American film debut as Wah Sing Ku.

Lorna Cole is pregnant with LAPD sergeant Martin Riggs' baby; they are not married, but both are thinking about it. Police sergeant Roger Murtaugh's daughter Rianne is also pregnant, and Riggs later learns from Lorna that Rianne has secretly married Lee Butters (Chris Rock), a young detective who works at the same precinct as Murtaugh and Riggs – secretly because Roger had made it clear that his daughter should not marry a police officer.

Riggs, Murtaugh, and Butters – with some assistance from Leo Getz (Pesci), who is now a private detective – investigate a Chinese immigrant smuggling ring after they come across a vessel with a cargo hold of Chinese slave laborers; in the course of these events Murtaugh's boat is sunk. Murtaugh finds a dinghy alongside with a Chinese family whom he provides shelter for at his house, claiming to be "freeing slaves."

Lethal Weapon is a 1987 American buddy cop action film and the first in a series of films, all directed by Richard Donner and starring Mel Gibson and Danny Glover as a mismatched pair of LAPD detectives, and Gary Busey as their primary adversary. After the first film, the series fell into the action thriller genres, and is generally considered to typify the "buddy cop" plot device.

L.A.P.D. Homicide Sergeant Roger Murtaugh (Danny Glover) is worried about getting old, having recently celebrated his 50th birthday. He receives a message from Michael Hunsaker (Tom Atkins), an old Vietnam War friend who Murtaugh realizes he has not seen in over 12 years. Before he can meet him, he is called to investigate a suicide and learns that the victim is Hunsaker's daughter, Amanda. Elsewhere, L.A.P.D. Narcotics Sergeant Martin Riggs (Mel Gibson), who is suicidal following the recent death of his wife in a traffic accident, nearly kills a disarmed suspect after flying into a psychotic rage during a drug bust. Wary of his behavior, Riggs' superiors transfer him to Homicide, making him and Murtaugh reluctant partners.

Li Lianjie ([lì ljǎntɕjɛ̌]; born April 26, 1963), better known by his stage name Jet Li, is a naturalized Singaporean film actor, film producer, Chinese martial artist, wushu champion, and international star who was born in Beijing.

After three years of intensive training with Wu Bin, Li won his first national championship for the Beijing Wushu Team. After retiring from Wushu at age 19, he went on to win great acclaim in China as an actor making his debut with the film Shaolin Temple (1982). He went on to star in many critically acclaimed martial arts epic films, most notably the Once Upon A Time In China series, in which he portrayed folk hero Wong Fei-hung.

Li's first role in a Hollywood film was as a villain in Lethal Weapon 4 (1998), but his first Hollywood film leading role was in Romeo Must Die (2000). He has gone on to star in many Hollywood action films, including Kiss of the Dragon and Unleashed. He co-starred in The Forbidden Kingdom (2008) with Jackie Chan, The Expendables (2010) with Sylvester Stallone, and as the title character villain in The Mummy: Tomb Of The Dragon Emperor (2008) opposite Brendan Fraser. He also appeared in the Hong Kong film Ocean Heaven (2010), directed and written by Xue Xiaolu.