Trivia: After the building collapses in the beginning, the bomb-squad guy who claps (making fun of Riggs's and Murtaugh's goof up) is in real life Bill Frederick, the mayor of Orlando at the time the scene was filmed.
Trivia: The building that explodes in the beginning of the film (due to Mel Gibson messing with the bomb) was the old city hall in downtown Orlando, Florida, where the scene was shot. In reality, only half the building collapsed from the explosion.
Trivia: Murtagh's boat is called "Code 7". This is the L.A.P.D. code for a lunch break.
Trivia: This is the only Lethal Weapon movie in which none of the villains ever enter the Murtaugh family home. It is also the only movie in which Riggs' deceased wife is never spoken about.
Trivia: The nurse who takes off Leo's watch in the hospital after he has been shot is played by Lauren Schuler-Donner, director Richard Donner's wife.
Trivia: Writer Jeffrey Boam is strangely credited three times in the writing credits. The credits read: "Story by Jeffrey Boam," and "Screenplay by Jeffrey Boam and Jeffrey Boam and Robert Mark Kamen." This is because of some strange rules among the studio and writers guild about how writers are credited. Boam was initially hired just to write the story and the first draft of the screenplay... but then he was re-hired by the studio later on to re-write his script with Kamen. Because he was technically hired twice (first as a solo writer than as a co-writer), the studio was required to give him multiple screenplay credits.
Trivia: Keep watching until the end of the closing credits for a bonus scene.
Answer: Billy was played by Mark Pellegrino.
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