As “Murtaugh” nears his retirement date, he and his partner “Riggs,” now sporting a ponytail, stop an armored car robbery and make an arrest. However, before any serious questioning can take place, the suspect is killed, and they are assigned by “Murphy” (Steve Kazan) to collaborate with IAD detective “Lorna” (Rene Russo) to find out who’s responsible. It doesn't take long for them to realize that their search leads to "Lt. Travis" (Stuart Wilson), who’s tangled up in an illegal gun operation. Their investigation becomes somewhat simpler when realtor “Getz” (Joe Pesci) believes he recognizes him, which kicks off a series of action sequences—explosions, gunfire, and car chases—during which “Murtaugh” experiences a profound sense of hopelessness that only his friend can help him overcome, as "Travis" has now made the situation intensely personal. The film shines brightest when it focuses on Gibson and Glover’s dynamic; the dialogue is sharp, and they share some witty banter. I didn't enjoy the developing relationship between “Riggs” and “Lorna” very much, and the only memorable thing about Pesci’s performance is his hairstyle. It’s a well-told story, directed in a way that maintains momentum while allowing the two leads to clearly have a good time. While I consider it the least impressive of the three films so far, it remains an enjoyable distraction.

Source on TMDB