KSite TV posted a synopsis for episode 1.21 of The Originals titled, The Battle Of New Orleans:
BLOOD IS IN THE AIR — Klaus (Joseph Morgan) and Elijah (Daniel Gillies) enact a plan to collect the sacred stones needed by Genevieve (guest star Elyse Levesque) in order to forever change the fates of Hayley (Phoebe Tonkin) and the werewolf community. Realizing that Klaus’ plan will lead to the extermination of all French Quarter vampires, Marcel (Charles Michael Davis) rallies an army determined to take down the Mikaelsons and regain control of the city. Davina (Danielle Campbell) warns Josh (guest star Steven Krueger) to leave town as she is forced to make a fateful decision that will turn the tide of war. Meanwhile, Francesca (guest star Peta Sargent) threatens Cami (Leah Pipes), who attempts to decipher a code that results in a surprising revelation among the city’s factions.