Rose Rosetti, the orphaned daughter of a New York gangster, and Danny Lewis, another orphan, have been brought up by Sara and Abraham Kamisnsky, an elderly Jewish couple with an artificial-flower shop on the lower East Side. Rose works in the shop and Danny, after defeating the ward-bully in a fight, joins the political gang. The Kininskys die, having told Rose of her real parentage, and will the shop to Danny and Rose. Danny, saved from the gang by Rose, falls into the clutches of Willifsky, a Bolshevik agitator, and his co-worker, Emma Goldstein. Danny falls in love with Emma and she uses him for the "cause." When the war with Germany comes, Danny will not enlist into the army. Willifsky and Emma are attacked by a crowd while they are agitating and Danny, in helping them, assaults a policeman. He also prevents her from throwing a bomb, and, after Galligan, a ward-leader, gets him exonerated, decides to join the army.