 There are eight actors who appear in all four Lethal Weapon films as  the same characters: Aside from Mel Gibson (I) (qv) and  Danny Glover (qv) as Riggs and Murtaugh, respectively,  Darlene Love (qv) plays Murtaughs wife, Traci Wolfe (qv),  Damon Hines (qv) and Ebonie Smith (qv) are Murtaughs kids,  Steve Kahan (qv) is Captain Murphy and Mary Ellen Trainor (qv)  plays the police psychiatrist, Dr. Woods. In addition, Riggs dog,  Sam, appears in Lethal Weapons 1, 2 and 4. A deleted scene featuring  him was reinstated for the directors cut of  _Lethal Weapon 3 (1992)_ (qv). So, in a way, hes the ninth regular  character.