Lock Up (1989)

"Lock Up" is a 1989 action film starring Sylvester Stallone as Frank Leone, a model prisoner nearing the end of his sentence who is transferred to a maximum-security prison run by a corrupt warden. Frank becomes the target of abuse and mistreatment by the sadistic head guard, Drumgoole, leading to a battle of wills between them. The movie explores themes of survival, loyalty, and standing up against injustice within the harsh confines of prison life.