When Riggs visits his father-in-law in prison, a walk down memory lane reveals an old secret about his deceased wife. Meanwhile Murtaugh tries to impress Captain Avery, and, united by the death of a mutual friend, Trish and Leo Getz try and solve a murder on their own
When Texas cop and former Navy SEAL Martin Riggs suffers the loss of his wife and baby, he moves to Los Angeles to start anew. There, he gets partnered with LAPD detective Roger Murtaugh, who, having recently suffered a "minor" heart attack, must avoid any stress in his life.
From the moment the brash and impulsive Riggs meets prudent, by-the-book Murtaugh, it seems as if this partnership is doomed. But after their first case together, both realise this arrangement might just work out after all - if only Riggs doesn't get them killed first.