Dead Men Walking is an independent 2005 zombie movie directed by Peter Mervis and written by Mike Watt. It features a zombie outbreak at a maximum security prison. The film can now be seen on the Sci Fi Channel in the United States.
A CDC worker, Samantha Beckett, is sent to the prison to give more information on Travis. Travis and the new inmates arrive at the facility and are put in a line where they are evaluated by corrections officer, Lieutenant Sweeney, telling them that he is top of the food chain in the prison. After noticing Travis coughing heavily and pale, he is sent to the infirmary. Another new arrival, Johnny, is sent to Warden Mahlers office. Mahler tells him not to do anything stupid or make guards angry. His story is the same that Travis had been telling others. The bitten guard dies and Mahler, Sweeney, Dr. Goring, Samantha and Johnny try to determine if the virus is real. Samantha examines Travis body and sees that the blood indicates he died at least hours ago, though Sweeney shot him just minutes ago.Sweeney, Jenkins and Mahler devise a plan to move through the building and gather all the uninfected staff to barricade themselves in the staffroom on the other end of the facility while the guards venture out to kill all infected. He also plans to leave all the uninfected inmates to die, much to Johnnys dismay. Johnny is sent back to the cell but on the way he knocks out a guard and takes his gun to run for the outside. ........
Source: Wikipedia