Twin brothers are serving in the French army during the Great War. Jacques, a private, leads his brother's company to attack when Honoré, a lieutenant, panics and flees. Jacques, dressed in Honoré's coat, wins a vital victory, but he is mistaken for Honoré and decorated for gallantry in his brother's name. Jacques assumes Honoré's identity and goes to Paris where he meets Honoré. Honoré, after a serious disagreement, plots to have Jacques murdered but is himself killed by mistake. Jacques finds happiness with Moira, Honoré's wife from a loveless war marriage of convenience. 'Honor First' was the first film Adorée and John Gilbert made together.