Step in the Arena is the fourth episode of the first season of the Netflix exclusive television series Luke Cage.
As he rescues a victim of Cottonmouth's vengeance, Luke remembers his earlier life and the conspiracy that led to his superhuman strength.
While trapped in the rubble, Luke Cage reminisces about his past as Carl Lucas and his incarceration at Seagate Prison, a private detention facility run by C.O. Albert Rackham. He befriends fellow inmate Squabbles, develops an attraction to psychologist Dr. Reva Connors, and is forced to engage in illegal ring fights by Rackham, and crossed paths with inmates Hernan Alvarez and Comanche.
Lucas and Connors plan to expose Rackham's activities, which includes allowing an illegal experimental procedure on inmates in exchange for reduced sentences. Rackham learns of this by torturing Squabbles to death, and has Lucas brutally beaten. Connors convinces Dr. Noah Burstein, the scientist conducting the experimental procedures, to perform the procedure on Lucas, a submersive "bath" designed to cause rapid healing. Rackham sabotages the experiment, and the resulting accident instead gives Lucas superhuman strength and invulnerability.
He escapes and adopts the identity of Luke Cage. In the present, Cage manages to pull himself and Connie out of the rubble and reveals his abilities to the media.