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Lethal Weapon is a tetralogy of American action movies/comedies, originally written by Shane Black and entirely directed by Richard Donner. The series starred Mel Gibson and Danny Glover as a pair of mismatched detectives in the LAPD. The first movie effectively defined the entire Buddy Cop Show genre. The unbalanced, unhinged Riggs was contrasted with calmer, stricter family man Murtaugh.In Lethal Weapon (1987), Glover plays Roger Murtaugh, the strict cop that plays by the rules, and worries about getting too old (for this shit). He is partnered with Martin Riggs, a suicidal badass despairing over the death of his wife. Riggs is well versed with both martial arts and gun play and added to his berserker tendencies makes him a candidate to be registered as a lethal weapon. They start tracking down a major drug dealer who has ties within the force.In Lethal Weapon 2 (1989), they received a comedy sidekick played by Joe Pesci as a witness and insider to the new bad guys. The Big Bad of the movie was Arjen Rudd, a South African diplomat using diplomatic immunity to hide behind drug smuggling.In Lethal Weapon 3 (1992), Riggs finds a new Love Interest in Lorna Cole (Rene Russo), a fellow cop who is as tough and crazy as he is. She helps them to investigate a rogue officer who's been selling specialized armor piercing "cop killer" bullets to the mob and onto the streets. Looming over Murtaugh's head is his upcoming retirement and trying to figure out his life as a cop and what it will be like after retirement.In the final installment, Lethal Weapon 4 (1998), Lorna is pregnant with Riggs' baby and both he and Murtaugh are contemplating the implications of growing older. Meanwhile, Riggs and Murtaugh receive a brash younger detective named Lee Butters (Chris Rock) and are dealing with Chinese Triads when they uncover a boatload of illegal immigrants. The Dragon (In Chief) /Big Bad of this group is Wah Sing Ku, played by Jet Li, by whom Riggs finds himself entirely outmatched.Each movie played out like a cross between the typical cop show and Indiana Jones, with spectacular stunts at a breakneck pace while following a chain of evidence.Now has a character sheet
The first movie, when Riggs has dinner with Murtaugh's family, the oldest daughter is making eyes at Riggs, and the attraction seems to come from this, especially when Riggs sides with her in a father-daughter fight over her marijuana use. As a result, Murtaugh is paranoid about his daughter and Riggs during the entire freaking series!!!
Artistic License – Gun Safety: Real life cops would never handle firearms as recklessly as Riggs and Murtaugh do. The only time it's arguably justifiable is in the first film, when Riggs was borderline suicidal and thus was pointing his gun at his own head on purpose.
Riggs' laser trick shooting in the start of 4 at the tanker, the laser sight going full out Frickin' Laser Beams
Also in the same scene, barrels of flammable liquid are not ignited by gunfire, and they do not detonate and launch like missiles using the bullet holes as exhaust ports.
As You Know: A police psychiatrist helpfully explains some of Riggs's backstory in the first film. Which is bizarre, considering that it's already established that Riggs is a widower.
"May I remind you that his wife of 11 years was recently killed in a car accident?"
Ate His Gun: Riggs is outright suicidal in the first film. In an early scene, he actually puts his gun in his mouth, but doesn't shoot. He also almost blows his head off with Roger's revolver, but is only stopped because Roger sticks his finger between the hammer and the chamber (in other words, if Roger was half a second later, Riggs would've been dead).
Avenging the Villain: Near the end of the fourth film Wah Sing Ku is attempting to flee Riggs and Murtaugh with his brother, all the other villains having been killed. When Murtaugh shoots Ku's brother while aiming for Ku himself, Ku sticks around and tries to kill Riggs and Murtaugh in revenge. Riggs then shoots Ku underwater after they fall off a pier while fighting.
Badass Boast: Riggs has several throughout, but his Establishing Character Moment in the first film really hits this trope hard: "When I was 19, I did a guy in Laos from a thousand yards out. It was a rifle shot in high wind. Maybe eight or even ten guys in the world could have made that shot. It's the only thing I was ever good at."
Bash Brothers: Riggs and Murtaugh don't embody this trope until the final fight against Ku in the fourth movie.
Bizarre and Improbable Ballistics: The "cop-killer" bullets that are the basis of the plot in III seem a tad inconsistent in their destruction; they are so powerful that they can not only punch through two sides of a steel drum AND a vest worn by Billy (killing him), they can even penetrate a bulldozer blade and its engine block to kill the Big Bad! However, Lorna's two bulletproof vests stop them dead. Somehow.
Bland-Name Product: The hockey teams playing at the Forum in Lethal Weapon 3 were obviously meant to be the Los Angeles Kings and the Toronto Maple Leafs. The colors are just about identical. Look closely enough at the right time, though, and you'll see they're wearing generic uniforms. If you pay attention, the film actually features stock footage of the Los Angeles Kings and the Toronto Maple Leafs. They apparently couldn't get rights to use at least real NHL uniforms for the scenes they filmed.
Bombproof Appliance: A bathtub. The MythBusters eventually tested this as in the scene, and aside from the detonation method (which actually took longer to go off), it all worked exactly as advertised.
The films are played quite frequently on TNT and TBS, which are infamous for censoring language in films. For someone who's familiar with the theatrical version of the first film, watching it on one of these networks can be quite hilarious for that very reason. Unfortunately, sometimes the censorship seems unnecessary and arbitrary— like when they cut out Riggs punching the guy on the hood of the car in Lethal Weapon 3 after asking if he was all right.
Also, in Britain the theatrical release of Lethal Weapon 2 cuts the scene where Riggs kills two of the villains who drowned Rika after he uses his Houdini impression to escape the same fate.
Chekhov's Nailgun has a longer run than you'd expect. In the third film, it reminds Murtaugh, who is trying to sell his house, that he forgot to get permits to repair his blown-up house!
After Murtaugh's daughter appears in a condom advertisement, Murtaugh bemoans how his police colleagues will be planting condoms wherever he goes. That night Murtaugh and his family are attacked in their home and no-one is interested in playing jokes on him...until later on in the movie when Murtaugh shoos away some cops crowding around his desk only to find they've planted a 'rubber tree' there. Even Murtaugh can't help breaking down in laughter.
Murtaugh was concerned about Rianne's flirtations with Riggs and the possibility she'd end up married to a cop. The latter happened, but not to anybody Murtaugh knew.
Bulletproof Vest: In the first Riggs survives a shotgun blast because of his vest (and complains endlessly about how much it hurt). Also used throughout the third due to "cop-killer" bullets on the street.
Call Forward: The musical riffs we first hear in the original film are later used in Sting and Eric Clapton's "It's Probably Me", the hit single from the third film.
Car Cushion: The first film opens with Amanda Hunsacker committing suicide by throwing herself off a balcony and onto a parked car below.
Career Building Blunder: After the third film, where Riggs and Murtaugh were busted down to patrolmen for messing with the bomb squad's job (and blowing up a building), the fourth film has the department unable to get their insurance renewed due to the propensity of the duo causing catastrophic damage in their escapades. But since they can't be demoted off the streets, the department decides to promote them, fully two steps, bypassing Lieutenant and making them both Captains, at least until the insurance is renewed, in an attempt to get them off the streets. The insurance gets renewed at the end of the movie, though, resulting in Riggs and Murtaugh being busted back down to Sergeants. Notably, while their escapades are just as frenetic and crazy as the last three films, they are not nearly as destructive, explaining why they were able to get the insurance renewed.
The SWAT team arriving about a minute or so after Riggs shoots the playground sniper near the beginning of the first film.
Subverted in the third film, where Riggs argues that the bomb squad never gets here on time!"; they meddle with the bomb, it goes off, a massive building is leveled... and the bomb squad immediately pulls up, having arrived in plenty of time to deal with the bomb had Riggs not interfered.
The machine gun loaded with "cop killers." Sold to Tyrone by Travis, who then sells it to Darryl, it is taken by Murtaugh when he kills Darryl. Later he uses it against the bad guys and finally tosses it to Riggs - who uses it to kill Travis.
Chekhov's Skill: Riggs' "trick" shoulder that can be dislocated more or less at will:
Riggs' ability to dislocate his shoulder is established in the beginning of the second film, where he uses it twice to get out of a straightjacket.
During the fight with Wah Sing Ku, after he dislocated Riggs' shoulder, Riggs gives him a short but brutal No-Holds-Barred Beatdown.
He also has to reset his shoulder twice in the third film, though not under such mortal circumstances. At one point, he slides himself into a pole to do so on the fly.
Cold-Blooded Torture: Riggs and Murtaugh are both subjected to this in the first film, as the bad guys try to find out from them what the police know. It doesn't work, because the cops don't know much of anything, and because Riggs is able to escape from Endo and go on a rampage.
Despite being a highly trained martial artist, Riggs isn't against groin attacks, using improvised weaponry, dropping a crate on a man, or killing him with a machine gun when it becomes clear he's not going to win a fist fight.
Lorna Cole isn't above using groin attacks either as evidenced in Lethal Weapon 3 when she grabs a man by his junk and pulls it upward rather painfully.
Murtaugh: When are you gonna learn you can't solve every problem with your fists?
Riggs: Well, I couldn't use my gun; there was a crowd.
Complexity Addiction: The South African villains send two helicopters full of machine-gun toting mooks to kill Riggs which fail conspiciously, only to later get the drop on him by just hitting Riggs over the head as he walks to his car.
Continuity Nod: Many scenes from previous films are mentioned throughout the series.
Perhaps the funniest continuity nod is in Lethal Weapon 3, in which Leo serves a realty agent trying to help Roger sell his house. Because of full disclosure issues, when the prospective buyers mention that they love the picture window, he says it's recently been replaced because a drug dealer crashed his car through it and shot the entire place up. (A reference to the first film, but see below). Then he has to mention the damage that happened in Lethal Weapon 2:
Leo Getz: The bathroom upstairs has been completely remodeled due to unexpected bomb damage.
Also, Riggs and Lorna flirting in the third film, Riggs mentions a 'whole family of .44s on the back' from where Arjen Rudd shot him at the end of LW2 and he also mentions the knife Vorstedt got him with in the leg at the climax.
Cop Killer: The South African government drug dealers assassinate several LAPD police officers to make them back off their investigation. Of course this just makes Riggs and Murtaugh more determined to defeat them. Riggs kills the assassin who killed them, and Murtaugh murders the government official who ordered the hit.
Crazy-Prepared: Not so much crazy as it was clever, but Lorna managed to survive a potentially fatal cop-killer bullet wound by wearing twoBullet Proof Vests just in case.
Creative Closing Credits: The fourth movie has pictures of the cast and crew with "Why Can't We Be Friends" in the background.
Da Chief: Captain Murphy, though he regards Riggs and Murtaugh's antics with weary exasperation, as opposed to always yelling at them like most examples of this trope.
Murphy: You know what? I don't give a fuck, okay? That's why I don't have an ulcer, cause I know when to say "I don't give a fuck."
Darker and Edgier: Although all of the movies contain a fair amount of humour and over-the-top scenarios, the first movie is generally a bit darker and more grim than the more cartoon-like later movies, focusing heavily on Riggs' suicidal tendencies and framing his out-of-control nature as borderline psychotic.
Death Seeker: A major theme of the first film is that Riggs wants to die, but cannot bring himself to commit suicide. Early on, he eggs a man who has taken him hostage to kill him.
Destroy The Product Placement: The car chase scene in Lethal Weapon 4 between the ’98 Pontiac Grand Am and a Mercedes Benz 420 SEL (with the former being driven by Roger and the latter by a criminal) ends with the Pontiac being partially damaged by crashing through an office and suffering some damage by a truck. That same truck ends up ramming the Mercedes Benz.
Did Not Die That Way: Martin's wife was said to have been killed in a car accident. Turns out in Lethal Weapon 2 that the "accident" in question was a deliberate hit-and-run by that movie's Big Bad that was meant to kill Riggs himself but got her instead.
Diplomatic Impunity: Arjen Rudd claims diplomatic immunity to make the heroes back off in the second movie. (Although in fact, he was only a consular officer, and they get a lower grade of immunity - unless he had some other official status as well, he could have been searched provided proper procedures were followed.) Probably the Trope Codifier for the trope's use in modern fiction. For extra ballsiness, at one point he does this while SHOOTING at Riggs. Murtaugh revokes it a second later.
Dirty Cop: In 4, Riggs confronts Murtaugh about this, asking how he can support his family, get his kids though college, rebuild his house and buy a fishing boat on a Sergeant's salary. Murtaugh is reticient, and this drives a wedge between them. It turns out that his wife has written several Mills and Boon Prose-heavy Romance Novels (Riggs describes them as "the cheesy sex novels") that sell extremely well, and he's been embarrassed about where the money comes from.
Disproportionate Retribution: Frequently inflicted upon Leo. Yeah, the guy's annoying, but is that any reason to break his nose, then grab said broken nose? Not to mention the proctological examination in the third movie.
The Dragon: Typically opposing Riggs. Mr. Joshua in the first, Pieter in the second.
Dragonin Chief: Wah Sing Ku in the fourth movie is technically working to free his bosses, one of whom is his older brother. But since they are all in prison he's the one who actually drives the plot.
Dragon Their Feet: In the first film, while General McAllister was barbecuing his nuts on Hollywood Boulevard, Mr. Joshua went to Murtaugh's house to go after Roger's family. But there was "nobody here but us good guys".
Eating Pet Food: In Lethal Weapon 3, Murtaugh helps Riggs quit smoking by feeding him dog biscuits.
"El Niño" Is Spanish for "The Niño": In the fourth film, when Riggs, Murtaugh, and Butters seek to question Uncle Benny at a dentist's office, they give him a dose of laughing gas to make him more complacent, except they give him too much gas, making him way too aloof and carefree to be very helpful. His one clue as to the location of the Hongs is "Yao Mihn Bi". When asked what that means, Uncle Benny explains, "'Yao Mihn Bi' means... 'Yao Mihn Bi'."
Electric Torture: Done to Riggs in the first film. Of course, he doesn't break, because he's the hero!
Embarrassing Middle Name: While interrogating one of Jack Travis's henchmen, Riggs reads out the name on the man's driver's license: Hubert Bartholomew Smith.
Lorna (impressed): Bartholomew!
Establishing Character Moment: Riggs is introduced by making crazy jokes during a sting operation, blowing a few mooks away, and then trying to commit suicide by crook. This all establishes him as a loony, badass Death Seeker, in complete contrast to the solid and serious family-man Murtaugh.
Even Evil Has Standards: Gangster Tyrone in the third movie is visibly disgusted at Jack Travis' disposing of a rebellious mook by burying him alive in wet cement.
Roger Murtaugh: You ever hear of Ebony Clarke? Martin Riggs: Yeah, she writes those cheesy sex novels... why? You boinkin' her? Roger Murtaugh: No I'm not boinkin' her, Trish is Ebony Clarke. Martin Riggs: So you are boinkin' her. Roger Murtaugh: [big grin] Yeah, Yeah I'm boinkin' her!
From the Mouths of Babes: The six-year-old witnesses to Dixie's house being bombed in the first film. "You're gonna bust Dixie! You're gonna bust Dixie!" Later, after the bombing: "My Mom says policemen shoot black people!" Mel Gibson looked like he was legitimately cracking up in that scene.
Subverted hilariously. In the third film, Riggs insists that he and Murtaugh go into the parking garage to try and defuse the bomb because "the bomb squad never gets there on time", as if that's a truism he's learned from experience or possibly from watching too many movies. After Riggs screws it up ("GRAB THE CAT!"), the bomb squad arrives seconds later. They would have had more than enough time to defuse the bomb if not for Riggs. They give him a sarcastic round of applause, too.
Played straight by Murtaugh in the same scene, who argues against messing with the bomb because he's only eight days from retirement and he doesn't want to do anything stupid.
Played straight in the first film by the bus driver whose car collides with McAllister's. He quickly backs the bus back several yards, just in case the car were to explode. Smart man.
Gilligan Cut: Murtaugh, stuck on the toilet, begs Riggs to keep his call to the bomb squad discreet. Guess what happens instead?
Give Me a Sword: Murtaugh tosses Riggs a nightstick in the fight with Mr. Joshua near the end of the first film, in response to the latter using a pole against him.
Good Cop/Bad Cop: Almost immediately after meeting Leo Getz in Lethal Weapon 2, Riggs tells him to shut up. Getz says, "Oh, I get it— good cop, bad cop." Then Murtaugh also tells him to shut up. "Okay... bad cop, bad cop."
Good Is Not Dumb: After Riggs is blown through a window by a shotgun in the first film (he was wearing his bulletproof vest, so he didn't die), he points out to Murtaugh that now the police have the advantage, because the bad guys think Riggs is dead. Sure enough, Mr. Joshua calls the police station for information about the shooting, claiming to be a news reporter. The officer who picks up confirms that Riggs is dead, and it never occurs to McAllister and Joshua that the police could be deceiving them.
Goofy Print Underwear: Murtaugh from 4; when directed by Riggs to strip to his boxer shorts to distract a madman wielding a flamethrower, Riggs asks with a laugh "Are those little hearts?"
Gory Discretion Shot: A mook is killed in 2 when a surfboard flies into his windshield and hits him in the face. Not much is shown but Rigg's squicked out facial expression says it all. It's also lampshaded by Captain Murphy later. "All I know is there is a guy in the morgue and he's got a surfboard where his face used to be..."
Groin Attack: In the third movie, Lorna Cole delivers a harsh kick in the family jewels towards a random thug from within a warehouse. Later on, she crushes one thug's testicles bare-handed in a fight scene!
Guns Do Not Work That Way: The idea that "cop killer" bullets are an option for the submachine guns seen in part 3 is nonsense. By the time you've juiced up, say, a regular 9mm with a sufficiently hardened bullet (just being pointy won't cut it) and enough propellant to punch through thick steel or kevlar, it's very likely going to explode that MAC10 you were hoping to feed it into. Best to just chalk the whole mess up to Rule of Cool.
Heavily Armored Mook: The flamethrower and machinegun wielding lunatic at the start of the fourth movie.
The fact that General McAllister has explosives in his car enables Roger to kill him (by killing his driver, causing an overturned-vehicle crash) in the first film.
Riggs stabs Vorstedt with his own knife in the second film.
Riggs kills Travis with a gun modified with cop-killer bullets (which Travis helped put back on the streets to begin with) in the third film. And it is in fact the very same gun used by the boy Murtaugh shot. Which Travis stole from LAPD impound and sold to the boy in the first place.
A more comedic example would be in the fourth film when Riggs wants to ask the psychiatrist for legitimate advice regarding his intent to marry Lorna, but his years of mocking her makes her instantly go on the defensive and assume he's trying to punk her again.
Honor Before Reason: In the climax of the fourth film, Riggs and Murtaugh had successfully thwarted the bad guys plans. But they killed Ku's brother, leaving him seriously pissed. They had more than enough time to make their exit and stay away from Ku's wrath and even begin to walk the other way, talking about coming back with a howitzer or something like it. But Riggs started musing about Ku's crazy gun dismantling trick he pulled earlier in the film and they realized they had to face him to end it.
Hope Spot: A tiny window for Riggs in 2. He and Roger survived The Purge, Riggs and Rika barely making it out of his trailer before they're blown to bits, he drops Rika off at her apartment, telling her to call in sick the next day, both looking forward to a life together. Then, Pieter and company arrive, knocking Riggs unconscious...
Hot Pursuit: Played straight to the point of parody to the point of subversion back around to straight, all in record time.
Hydrant Geyser: At the end of the first movie one of these creates the mood for the climactic fist fight scene between Riggs and Joshua.
Iconic Sequel Character: Joe Pesci's Leo Getz character first appears as a federal witness in the second film, and manages to show up in the rest of the series' films.
In Lethal Weapon 2, no one thinks that Miss Van den Haas will need protection from her evil employers that she just betrayed and who just tried to murder both her and Riggs. They simply drop her off alone at her home, where the villains already know she lives. Rika herself grabs hold of the ball by not seeing the fatal flaw in this plan, and it gets her a one-way trip to the fridge.
Also Arjen Rudd in the second movie. Near the end of the movie he starts to shoot at the policemen and claims diplomatic immunity that can protect one from being arrested but not, you know, from being shot in self defense. Had he refrained from shooting, the protagonists could have done nothing without provoking a major international incident.
Riggs pulls off some incredible shots. Sure, Murtaugh has his share, but Riggs was breast-fed on this trope. The sniper in the school, being able to shoot a smiley-face on the firing range, being able to successfully hit a helicopter God knows how many yards away, etc. all with a pistol. And then picking off Shadow Company mooks like flies. And that's just the first film.
In part 2, Riggs fatally shooting the pilot of a helicopter in the dark from about 100 yards away. With a pistol.
The "have-a-nice-day" moment in the first film. Murtaugh lampshades Riggs' improbable aiming skills perfectly:
Murtaugh[re: Riggs' gun]: You sleep with that thing under your pillow or something? Riggs:I wouldif Islept.
Murtaugh isn't a hot-shot gunslinger, but if he carefully aims his gun and rolls his head to loosen his neck before squeezing off a shot, he'll hit with perfect accuracy. He pulls off an excellent shot to kill the Big Bad of both parts 1 and 2. In part 1, he shoots the driver of a car coming right at him, and then gets out of the way as the out-of-control car goes flying onto Hollywood Boulevard and smashes into a bus. And in part 2, he revokes Rudd's diplomatic immunity with a damned impressive head shot.
Insane Troll Logic: In 4 when Riggs and Murtaugh are looking for the Triad thugs who just tried to kill them, they ask a chopper to look for the car they took off in. A black Mercedes on a certain part of the freeway. The chopper says they've got two cars that match that description, one heading east, one heading west. Riggs, who's driving, says they're following the one heading East.
Murtaugh: "How do you know we're chasing the right one? Riggs: "I don't know, but we're going east, and China's east, so..." Murtaugh: "Yeah, but China's west too, Riggs."
Interrupted Suicide: Riggs goes to shoot himself with Murtaugh's revolver, but Murtaugh sticks his thumb in front of the hammer as it comes down, preventing the firing mechanism from finishing its task and setting off the bullet that would have otherwise ended Riggs' life.
It's Personal: Each movie eventually turns into this. Riggs even says the trope by name in part 2.
Jerk Ass: Alas, Riggs and Murtaugh in the third movie, particularly towards Leo Getz.
Parodied in the third film, when Riggs threatens a belligerent jaywalker with killing him and making him look like a suicide. After the man scurries away, Riggs and Murtaugh laugh about it.
In the second film, Vorstedt reveals that Riggs' wife's death was not an accident as it appeared and was ruled; Vorstedt sabotaged the brakes to make her car go off the road, as he was trying to kill Riggs himself (who was not in the car).
Man Child: Riggs has elements of this. He watches Looney Tunes, even while contemplating suicide, as well as The Three Stooges, and is generally adolescent in nature.
Mauve Shirt: All the new detectives introduced in the second movie. The 22-year-old cop, Edwards, who's the butt of jokes at his expense about his age and height throughout the third film, and takes it all with good-natured, innocent charm. He ends up dead at the hands of Jack Travis.
Meaningful Name: Leo tries to make this work for him. (And mostly just ends up annoying people.)
Leo Getz: My name's Leo Getz. Whatever you want, Leo gets. Get it?!
Meet Cute: A platonic example. When Murtagh sees scruffy, wild-eyed Riggs in the police station, and Riggs draws his gun, Murtagh thinks he's a criminal and tackles him.
Also in the fourth film with Wah Sing Ku who is younger than both Riggs and Murtaugh and very skilled in a deadly form of martial arts.
One-Man Army: Riggs for the first three films, untl his age finally catches up to him in 4. The only guy he has trouble with in 4 is Jet Li's character.
Outranking Your Job: The fourth film has Riggs and Murtaugh both promoted to captain, but the promotions seem to carry no real weight. Neither is assigned any subordinates or additional responsibilities, and aside from Riggs occasionally announcing, "This is your Captain speaking!" to colleagues, both continue to chase criminals as if they were sergeants - this though the whole point of promoting them was to get them out of the field.
Ooh, Me Accent's Slipping: Mel Gibson has this problem, especially in the earlier films. Note the "gold pen" speech in the second film for an example.
Overly Long Gag: The target takes a long time to get to the end of the range, and a long time to come back.
Papa Wolf: Murtaugh is fiercely protective of his family, but particularly his daughter Rianne. He even punches Riggs right in the face (and overboard) after Riggs says "I think I may have slept with someone I shouldn't have," leading Murtaugh to assume he was talking about Rianne. He was talking about Lorna. Granted, he was drunk at the time.
This is the culmination of three films worth of tension. Murtaugh has always been protective of Rianne, and has worried that Riggs might "go for her".
Literally. Riggs went from Ax-CrazyDeath Seeker to Bunny Ears Cop when he chose to make friends with a guard dog instead of shooting him. He justifies it by saying that, while he's okay with shooting people, he's unable to shoot a dog. This probably would've been in effect even in the first movie.
In the first film, Riggs gives an adorable prostitute $100 just to come home and watch television with him.
Platonic Prostitution: Riggs in the first film pays a prostitute $100 just to watch TV with him, and not for the more traditional purpose of hiring a hooker.
Playing Gertrude: Murtaugh's comments to Riggs in earlier movies suggest he's at least 16 years older than Riggs, possibly 20 or more. He's clearly stated to be well over 50 in the first movie when Danny Glover was only 43 and only 10 years Mel Gibson's senior.
Plot Hole: When Riggs and Murtaugh head to the desert to free Murtaugh's kidnapped daughter in the first film, Riggs is dropped off with a sniper rifle and takes up position on a ridge several hundred yards away, overlooking the events. At this point, the Big Bad and his cronies believe Riggs is dead. Yet within a few seconds of Riggs opening fire on the antagonists, the Big Bad has ascertained Riggs' exact location and managed to sneak up behind him and put a gun to his head.
Compounding this is the fact that Mcallister doesn't immediately kill Riggs, despite the fact that he had Mr. Joshua try to gun him down in cold blood the previous day. If the villains only need Murtaugh taken alive for interrogation (And Joshua outright states this to Riggs after his capture), why bother to capture Riggs at all?
Also, near the end of the film, Riggs is chasing down Mr. Joshua on foot, Joshua commandeers a car and escapes, Riggs has to then run all the way back to Hollywood Boulevard to find Murtaugh, who realises that Joshua will seek revenge against his family. Bearing in mind that Joshua has a massive head-start and knows exactly where he is going, the heroes still get to Murtaugh's house so far ahead of Joshua that they have time to evacuate everyone and set up an overly-elaborate trap which involves destroying the front of Murtaugh's house with an unmanned squad car. How did they get there so much quicker than him and why didn't they just have the plethora of uniformed cops they have with them draw down on Joshua and arrest him as soon as he rolled up? (Glaringly, their Rule of Cool approach to his capture costs two lone uniformed officers their lives, when Joshua guns them down on arrival at the house.)
Plucky Comic Relief: Leo Getz in all movies after the first, but manages to stay out of Scrappy territory because Riggs and Murtaugh annoy him just as much as he annoys them.
Private Military Contractors: One of the most evil examples in film: the General and Joshua's heroin network is staffed and run almost exclusively by former Special Forces members who are now just in it for the money. The novelization expands it even more: they also employ Irish, Arabs, Germans, Russians, South Africans, Israelis...
The Purge: The villain in Lethal Weapon 2 does this to the LAPD detectives investigating him, with Riggs and Murtaugh the only survivors.
Psycho for Hire: Mr Joshua has no compunctions against killing or torturing anyone that might interfere with his job as a hired gun.
Reality Is Unrealistic: The Mythbusters tested the scene in the second film where Riggs and Murtaugh survive the toilet bomb by diving into the tub with a bomb blanket. The method would have worked, however, it was found that spraying the bomb with nitrogen would have given the characters a full fifteen minutes of time.
Redemption Quest: The entire series is one for Riggs. Murtaugh had his in the third movie after killing a teenager in self-defence.
Red Oni, Blue Oni: Riggs as the Red and Murtaugh as the Blue in the first three films. By the fourth film, Murtaugh is still a Blue Oni while Riggs is more of a Purple Oni, and Lee Butters is the Red Oni.
Riggs in the second movie, when he finds out that the South Africans killed his wife and his current girlfriend. Good thing Murtaugh was there...
Not quite as vicious, but when Murtaugh returns after Darryl's funeral in the third movie, he goes person-to-person shaking people down to trace his gun. At the first one's house, the home of one of Darryl's homeys, he rants about how gang-banging is tantamount to self-genocide for their race.
Also Getz has a different job in every movie (an accountant in II, a real estate agent in III, and a private investigator in IV).
In the second film, Riggs and Murtaugh are always telling Leo to stay in the car, which he almost always ignores. The one time he does what he's told, two bad guys commandeer the vehicle and kidnap him.
Riggs and Murtaugh can never agree on whether to go on three, or go after three.
Until near the end of the fourth film, when they're in perfect sync to pull the rubble off the nearly-drowning Riggs on a finger count.
Riggs will always find an excuse to go after criminals on foot, despite the fact that they are usually escaping in a vehicle.
And speaking of vehicles, Murtaugh and Trish's Station Wagons getting wrecked. Averted in 3, when Riggs and Murtaugh send in Da Chief's car, as an unmanned distraction, which absorbs hundreds of bullets for the cause.
Murtaugh: What's the plan? Riggs: Wait for my signal, then just go in and shoot those fuckers.
Shoot the Dog: After the guard dog befriends Riggs in the third movie, Hatchett yells for someone to "Kill that damn dog!"
Shoot The Television: Mr. Joshua does this in the first film after A Christmas Carol gets on his nerves.
Shooting Gallery: In the first movie, recently-teamed partners Riggs and Murtaugh are trying to one-up each other on the range. Murtaugh, annoyed at Rigg's tight bullethole group, sends a target further down the range and puts a single bullet through its 'head'. Riggs then sends his target all the way downrange, and shoots a smiley face in the head zone.
Suicide by Cop: Riggs attempts suicide by crook early in the first film, when he screams at a man who has taken him hostage to kill him. When the man takes too long, Riggs just grabs his gun and beats him up.
Stealth Pun: In the second film, when Murtaugh and Riggs are sitting in the bathroom and Roger is worried he's going to die on the toilet. After Riggs tells him that guys like him don't die on toilets, he adds:
Riggs: Besides, I'm here, and I have no plans on going right now.
The Stinger: Complimenting the scene in Genre Savvy, Riggs and Murtaugh arrive at a building where a bomb had been discovered. They discuss again or not to go in... and just as they stop at the building, it explodes and both leave as Riggs states "I hope nobody saw us".
Stuffed In The Fridge: The original plan for Rika in the second movie was for her to survive and attend the Thanksgiving party at Murtaugh's house with Riggs. Instead, she was killed off just so Riggs would be properly "motivated" for the rest of the movie.
Super Speed: In the 4th movie they had to get Jet Li to slow his fight scenes down because he was too fast for the actors to react to and the camera to catch on film.
Survival Mantra: "We're not too old for this shit... we're not too old for this shit..."
Suspiciously Specific Denial: In Lethal Weapon 3, Riggs gets ahold of one of Jack Travis' flunkies at the garage in which he works, asking him "where's your buddy Travis?" After Lorna is waylaid by five other guys (and beats the crap out of them) while Riggs, Murtaugh and the original suspect watch, Riggs again asks the suspect where Travis is. "I told you, I don't know a Jack Travis." "I didn't say his name was Jack."
Riggs: You better start telling me more than jack shit.
The third movie has Riggs suck-starting the flow of gasoline from a fuel tanker. When he gets a mouthful of gas, he spits it out and goes "Ugh, Exxon!". The film was produced shortly after the Exxon Valdez disaster in Alaska.
Lethal Weapon 4 contains some shockingly unsubtle jabs against the NRA. A bit hypocritical coming from a series that elevated dangerous and irresponsible gunplay to an art form.
In the first film: When Riggs, Murtaugh and Lianne escape from the boiler room, they make their way to the main room of a nightclub. A guy holding a gun turns to face them and Riggs shoots and kills him almost instantly. It's very loud. No one seems to notice. He kills two more people in the nightclub, and no one reacts until the third kill.
Earlier in the first film, this is averted when Hunsacker screams at Murtaugh to "KILL THEM! JUST KILL THEM!" Several people in the background briefly look in his direction.
Villainous Valour: Only Wah Sing Ku is able to disassemble a Beretta in 5 seconds with his own bare hands and then knocking off Riggs and Murtaugh who are older and taller than him. In the final showdown he once again manages to handle them even if they are two vs one.
What Happened to the Mouse?: The third Four Father must have somehow disappeared when the other two Four Fathers were being shot by the General in the fourth movie before the final shootout and when Ku and his brother fled.
"I was driving before you were an itch in your daddy's pants."
Wire Dilemma: Occurs in the third movie... and the bomb goes off.
The Worf Effect: Done interestingly in the fourth film. Riggs realizes his age when the primary henchmen on the boat handily kicked his ass. But Ku ends up dispatching that henchmen with embarrassing little effort, proving that he will be quite an enemy to beat.
In the second movie, after Rudd's henchman Hans loses a million dollars worth of gold Krugerrands. Rudd summons him to a room with plastic sheeting over the floor and has him executed. Echoed in a scene later on, when Pieter Vorstedt meets Rudd in his office after a failure. Pieter looks down at his feet during the conversation and comments, "I am just checking to make sure I am not standing on plastic."
In the third film Jack Travis, does this to both guys who attempted the armored car robbery, because they were "going into business for themselves" and running the risk of screwing up the entire operation. He has one of them drowned in cement and left to be paved over, and then goes into an interrogation room and shoots the other one in the head.
Wah Sing Ku does this in the fourth film, both to the freighter captain for losing the Hong family (as well as the entire shipment of Chinese), as well as Uncle Benny for generally disappointing him.
You Just Ruined the Shot: Riggs tries to save Rianne from what he thinks is a hostage situation, but turns out to be a scene in the movie she's in.