Mansour (Hossein Yari) is guilty of murder, awaiting the decision of whether or not he will be executed. His fate does not fall in the hands of a judge, though. It falls to the family of the man he murdered; if they ever make it down to the prison to make the call. Under Iranian law in cases of capital punishment, it is up to the victim's family to either condemn the offender to hang or save him with their forgiveness, but they are required to appear on the day of execution to officially select their verdict. Mansour has already faced the day of his sentencing a few times, and each time the judgment has been postponed due to the family's absence. And so he continues to wait for his appointment with death.
Anyone familiar with existentialist Iranian cinema can predict how Day Break ends, but it doesn't really matter if Mansour lives or dies. He is like Schrodinger's Cat, simultaneously alive and dead and neither state all at the same time. Trapped in a form of limbo, he endures the psychological struggle with having an indefinite future and a definite lack of free will. The torture of not knowing, for Mansour, becomes far worse a punishment than death.