Johnny Basil

Johnny Basil aka Desmond "Zil" Mobay, played by Lance Reddick, is a character on the HBO drama Oz.

An African American police detective, he is an undercover narcotics officer working under the false identity of Desmond Mobay and trying to bust the drug trade in Oz. "Mobay" is a Jamaican who wishes to work for the gangsters within Oz. Basil gets too deep undercover, and in the process of attempting to prove his loyalty to the gangsters, he becomes a heroin addict himself and kills an incarcerated police officer. Later, after being confronted by Augustus Hill, he confesses to the murder. He serves time in the police unit of Oz, Unit J, where he is eventually killed by Clayton Hughes, an incarcerated former correctional officer.

Basil arrives prepared to join with the Homeboys, the African American drug dealers within Emerald City. He gets a job as the Warden's assistant to keep the Warden informed and to have unmonitored access to phones and computers; with these, he regularly emails his partner, Nancy Mears, and his supervisor about what is happening within Oz. Warden Leo Glynn is, initially, the only person in Oz who knows of Basil's true identity, and he warns him about a similar operation that took place before, resulting in the murder of the undercover cop, Paul Markstrom. Glynn also warns Basil that he is not allowed to use drugs. Basil tells Glynn not to worry and that undercover narcs have ways of faking it. Plus, he added, half of the inmates are already high so they won't know the difference. Later, it turns out that Basil underestimated the inmates, especially Simon Adebisi, Enrique Morales, and Chucky Pancamo, the big three who don't use drugs.

In a deleted scene, Sister Peter Marie is the other person who knows about Basil's true identity. She visits Glynn because she was concerned that Mobay was a drug addict. Glynn asks Basil to come into the room and tells Sister Pete that he is an undercover cop. She says that he is very convincing and tells him to be careful.

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