AnnieWalker(PiperPerabo)isajuniorspystillintraining,whoissuddenly"promoted"tofieldagentbytheCentralIntelligenceAgency.Whileherexceptionallinguisticabilitiesmaybeonereasonhersuperiorsvalueher,it'snotthemostimportantone–herbossseemsmoreinterestedinsomeonefromherpast(anex-boyfriend).ChristopherGorhamportraysamilitaryintelligenceoperativewholosthiseyesightduringamission,andbecomesAnnie'smentorandhandler.AnneDudekplaysAnnie'ssister,amotheroftwo.KariMatchettportraystheheadoftheCIA'sspecialoperationsdivision,theDomesticProtectionDivision.PeterGallagherplaysherhusbandArthur,headofanotherspecialoperationsdivisionwithintheCIA.