A Russian woman assumes her twin's identity when the sister is mistakenly killed in her stead. Her rouse is uncovered when her sister's body is found. The living sister had been involved with a criminal element who wanted her dead. When the woman switched identities, she took on the more virtuous persona of her sister. Once she is discovered, her deception threatens to destroy the "marriage" she has enjoyed with her sister's husband and her efforts to free her younger sister who has been enslaved by her former criminal cohorts.