Level 4, also known as Four, was one of the eight levels in one of the Imperial Prison Complexes on the moon Narkina 5. In 5 BBY, a prisoner from four was mistakenly transferred to unit two-five on Level 2 after finishing his sentence, instead of being sent to another facility, revealing to the prisoners in the unit that they would never be released, only transferred elsewhere. The Imperials used the prison's electrified flooring to kill all one hundred men in the unit to keep them quiet, but word still ultimately got out and led to the other prisoners rising up and taking over the prison before escaping.