'Leave on word of honor' would be the correct translation of this title.
'Parole' sounds like they did something wrong, which they didn't, unless risking your neck for your country is wrong.
The Russian front having collapsed in the wake of the Bolshevik revolution, German troops are being transferred to the west, and when their train is forced to lay over in Berlin for several hours, the commanding officer risks court martial by giving his soldiers time to visit their families.
Will they return in time or desert ?