Mark Mack was an Aryan inmate featured in Oz. Portrayed by Leif Riddell.
"Prisoner number 96M542, Mark Mack. Convicted June 1, '96 - Murder in the second degree, vandalism, hate crimes. Sentence: 70 years, up for parole in 40." Mack is a member of the Aryan Brotherhood. Imprisoned for vandalizing a Jewish tombstone with a swastika and murdering a black man working in the cemetery, he is an enforcer for the Brotherhood who follows orders of leader Vernon Schillinger without question. Mack is hard-headed and bullies various inmates around. This eventually gets him killed as he is escaping, when he bullies some inmates to let him use an escape tunnel they were building.
Mack primarily existed as a background member in this season. He often mocked black inmates such as the Muslims during prayer time, and inmate Tobias Beecher for becoming Schillinger's sex slave. He left Beecher alone after he attacked Schillinger, however, and followed by participating in the riot led by inmate Kareem Said. After the riot, Mack joined the rest of the inmates in General Population as "Em City" was destroyed.
As Em City is reopened, Mack is one of the four Aryans allowed in. He represents the Aryans at the council meeting and attends a new education program started by Unit Manager Tim McManus. Schillinger then asks Mack to kill Beecher, who is trying to ruin his chance for parole. Mack refuses, however, because he fears confronting the increasingly unstable Beecher. Beecher is successful in ruining his former tormentor's parole and Schillinger is later beaten by some random black inmates in General Population. Schillinger, who believes he was attacked because no one fears the Aryan Brotherhood anymore, says they need to kill a "Mutt" (non-white person) to prove themselves again. Mack and Schillinger target Alexander Vogel, killing him and carving the word JEW on his chest. Several inmates, such as Miguel Alvarez, congratulate the Brotherhood whose reputation is for the time being restored. Mack then forces Richie Hanlon, a gay inmate, to perform oral sex on him, and then rapes him. Hanlon is then targeted by the other Aryans, but this stops after he kills one who attempts to sodomize him. As Hanlon is being investigated, he tells McManus that Mack killed Vogel as a means of getting off for the murder charge. The Brotherhood is furious, and they get officer Karl Metzger, an actual Brotherhood member, to force Hanlon to confess to killing Vogel. Now in the clear. Mack later finishes in the GED program and then sarcastically cheers on class valedictorian Arnold "Poet" Jackson, a black inmate who gets paroled merely to come back to prison a short time later.
Busmalis and cellmate Bob Rebadow plan to escape through the tunnel they have been digging, but the plan is thwarted when Mark Mack watches Busmalis at night disappearing into the ground beside his toilet. Mack and an Aryan friend investigate the cell and find the tunnel by stomping on the tiles while Busmalis and Rebadow are out for the day.
Mack, with the help of Aryan CO Karl Metzger, forces the old men to trade cells so he can escape instead. The old men agree, but before they leave, Rebadow encourages Busmalis to weaken the beams throughout the tunnel, ultimately resulting in the collapse of the tunnel and the death of Mark Mack and his unnamed Aryan ally. When the tunnel collapses, the prisoners within this unit are dragged from their beds to stand in line while the bodies are removed. Busmalis and Rebadow are brought before McManus, who sees no reason to discipline the two old men after hearing Rebadow explain that Busmalis never dug the tunnel out of free will, but was forced to by Mark Mack.