The Nice Guys (2016)

A young boy named Bobby witnesses a car crash and finds a dying woman named Misty Mountains. Suddenly, Misty's unconscious body is removed from the wreckage by a mysterious woman, preventing Bobby from acting as a witness.

Meanwhile, private investigator Holland March receives a case from a client named Mrs. Glenn, who claims to have seen her late porn star niece, Misty Mountains, alive and wants March to find her. March takes the case, but before he can make any progress, he is confronted by Jackson Healy, an enforcer hired to intimidate March into dropping the case.

Unbeknownst to both March and Healy, Amelia, a politically involved young woman, hires an amateur private investigator named Sid Shattuck to find a missing girl named Chet, who is connected to Misty's disappearance. Sid contacts March, mistakingly believing he's someone else, and arranges a meeting. However, shortly after their conversation, Sid is killed by John Boy, a professional hitman who wants to keep Amelia and Misty's secrets hidden.

March and Healy unexpectedly cross paths again at Mrs. Glenn's house, leading to a violent encounter. However, once they realise they're both investigating the same case, they decide to work together. They attend a party where Amelia is rumored to be, and although they don't find her, they discover that the party was organized by an automobile manufacturer named Mattress Man, who has ties to the Justice Department.

The duo later infiltrates the Department of Justice, successfully stealing documents related to Amelia and Misty's involvement in a scandalous porn film promoting the new catalytic converters, which were discovered to cause air pollution issues. Alongside a government agent named Tally, who is secretly helping March and Healy, they discover that Amelia has been hiding with her mother, who confirms that the film was financed by a Detroit automaker, and they have been eliminating witnesses.

With this new information, March and Healy head to the film's producer's house, only to find her dead and Amelia missing. They track Amelia to the house of the hitman John Boy, where they witness him being killed by Tally, who is revealed to be a corrupt agent. Tally explains that Amelia's mother is dead and Amelia is the last remaining witness, making her a target.

March and Healy rescue Amelia, taking her to the hotel where they left March's daughter, Holly, for safety. They are followed by Tally and his men, who launch an assault on the hotel. In a chaotic shootout, March, Healy, and Amelia manage to fend off their attackers.

Cornered, Tally reveals that Amelia was the mastermind behind the catalytic converter scandal, using the porno as a guise to expose the corrupt automaker industry. However, Misty discovered Amelia's plan and stole the film reels as insurance. Realizing Amelia's motive, March decides to help her.

They set up a meeting with the auto manufacturers, planning to expose their wrongdoing. However, the manufacturers double-cross them and deliver Amelia to a hitman. In a bold move, March crashes his car into the hitman's vehicle, causing an explosive collision.

In the aftermath, Amelia survives and the auto manufacturers are arrested. March and Healy attend a school play starring Holly, expressing their newfound respect and friendship for each other. As the movie ends, Bobby, who witnessed the whole ordeal, sets his sights on becoming a private investigator.

In the final scene, Misty Mountains is revealed to be alive and well, having faked her own death. She receives her payment for playing her part and leaves, signifying the unscrupulous nature of the people involved in the whole conspiracy.