Stone Cold (1991) on Netflix

Joe Huff is a cop who is angry at the system for handling criminals with kid gloves. Joe is on suspension, but the FBI gives him an opportunity to go undercover in Mississippi and infiltrate "The Brotherhood," a white supremacist biker gang that runs drugs. In the Brotherhood, each member legally changes his name to his Brotherhood nickname. The Brotherhood is led by a violent psychopath named Chains Cooper. Joe -- rechristened "John Stone" -- accepts the job, even though he's not happy about it. His FBI contact, Lance, doesn't really look at home in biker bars. And the members of the Brotherhood, especially Chains, have their doubts about Joe, who wants a piece of their action. Joe has to kill a man as his initiation. With the FBI's help, he carefully fakes a murder and is accepted by everyone except for Chains's right hand man Ice, who still thinks Joe's an undercover cop. Joe befriends Chains's girlfriend Nancy, and when Joe learns that Nancy is not happy being with Chains, Joe offers to help her escape. Ice finds Joe meeting with Lance, and tries to warn Chains, but Ice is killed in a fiery motorcycle crash before he can get to Chains. Nancy is later killed by Chains, and the man Joe is supposed to have murdered turns up alive, blowing Joe's cover. Chains and his gang later take the Mississippi supreme court hostage in an effort to stop one of their men, Trouble Owens, from being sentenced to be executed for killing a priest, and it's up to Joe to end the situation.