Unknown to her, Mary Manchester is a double for the ailing Mrs. Adelaide Rutherford, a wealthy woman who has been driven insane by her husband's cruelty. Rutherford is in league with Jasper Haig and Dr. Babcock. Together these men hold in trust sixty million dollars which upon Adelaide's death will revert to her brother Stanford Gorgas. Fearful of Adelaide's imminent death, the conspirators plan to substitute Mary in her place, thus preventing Gorgas from inheriting the money.