The protagonist in this play is Harry Van, an outgoing man who brings the other characters together and elicits their stories. A significant part of the plot concerns his past relationship with Irene and their fond memory of the night they spent together.
The antagonist here is Achille Weber, who stands between Harry and the object of his affection. Achille is an arms dealer; Sherwood implies that it is this segment of the population that is responsible for the war (because Achille profits from the sale of arms). Achille is a foil to Harry's outgoing and personable nature. He says little except for some secrets he exchanges with Irene, and in the end he cares only for himself. Not only does he withhold information from the other characters regarding the development of the war, but he also leaves Irene in the end to die while saving himself.