Lethal Weapon 4 is a 1998 American buddy cop action film directed and produced by Richard Donner, and starring Mel Gibson, Danny Glover, Joe Pesci, Rene Russo, Chris Rock, and Jet Li (in his international film debut).

The officers, along with Leo Getz, come upon a Chinese immigrant smuggling ring after running an oceangoing vessel aground, though the captain of the boat escapes.

In the subsequent investigation, Murtaugh finds the Hong family hiding from US Immigration officers to avoid deportation.

Continued investigation of the smuggling ring leads the officers to "Uncle" Benny Chan, a crime boss operating from a Chinatown restaurant.

Ku and the Triad thugs kidnap the Hongs, tie up Murtaugh, his family, Riggs, and Cole and set the house ablaze.

New information leads them to the abandoned warehouse where they find the bodies of Hong, his uncle, and Chan, the latter two killed by Ku after they served their usefulness.

Murphy gives Riggs and Murtaugh their rank of sergeant back since the city is insured again and Hong's family is granted asylum.

In addition, series regulars – who appear in minor roles in all four films of the franchise – include: Damon Hines and Ebonie Smith as Murtaugh children Nick and Carrie, respectively; and Mary Ellen Trainor as psychologist Stephanie Woods.

His first draft was completed in January 1995, focusing on Riggs and Murtaugh fighting neo-Nazi survivalists committing terrorist attacks on L.A., including using Stinger missiles to attempt to shoot down a jet carrying the Los Angeles Lakers.

[9][10] Peter Bart's book The Gross: The Hits, The Flops -- The Summer That Ate Hollywood offered many details regarding Lethal Weapon 4's troubled production, from writing to release.

Alfred Gough and Miles Millar wrote one of the unused scripts; they would be credited with Lemkin for the story of the finished film.

Silver ultimately brought in TV writer Channing Gibson to work on the script, after he was impressed by Gibson's rewrite of a spec script titled Sandblast, an action adventure thriller by screenwriter Steven Maeda described as "Die Hard (1988) meets Cliffhanger (1993)".

When they started filming the police station scene between Riggs, Murtaugh, Leo, and Butters, everyone felt the character did not work.

The two only share one scene in the final film with no written dialogue, due to last minute changes made to his character.

Besides Lemkin, Gibson, Gough and Millar, other writers did uncredited work on the script, including Michael Curtis, Greg Malins, Fred Dekker (who came up with the scene where Riggs and Murtaugh drive their car off the freeway and through the building), and even Boam was brought in to work on the script.

Due to issues during filming, including the script changes, production ended around mid May, less than two months before its scheduled July release.

The website's consensus reads: "Jet Li's arrival breathes fresh life into a tired franchise formula -- but not enough to put Lethal Weapon 4 on equal footing with its predecessors.

"[18] Metacritic, which uses a weighted average, assigned the film a score of 37 out of 100, based on 21 critics, indicating "generally unfavorable" reviews.

[19] James Berardinelli gave the film three stars out of four, writing: "Given the expectations that constrain it, Lethal Weapon 4 is probably the best motion picture that could possibly result from another teaming of Martin Riggs and Roger Murtaugh.

The series has lost a lot of steam since the first two entries, and, although the fourth movie ratchets up the energy level from the moribund state of the disappointing Lethal Weapon 3, there's no sense of spontaneity.

"[21] Michael O'Sullivan of The Washington Post called it a "stupid and violent delicacy" that balances a "patented blend of high action and low comedy".

There had long been talk of a fifth Lethal Weapon film, although both Mel Gibson and Danny Glover had initially expressed a lack of interest.

Donner said that he and Lethal Weapon 4 writer Channing Gibson "had an incredibly strong story for the fifth movie" but that the studio had opted to work with Joel Silver instead.

[30] In November 2017, Mel Gibson hinted that a fifth movie might happen and that he, Richard Donner, and Danny Glover have discussed the idea to return.

In December 2017, Donner confirmed in an interview on the Spocklight podcast that Gibson and Glover have agreed to return as Riggs and Murtaugh respectively and that he has a story all set.