Bella Donna falls for the exotic Baroudi and plots to poison her husband.

Bella Donna ( Pauline Frederick ) a seductive woman snares Nigel Armine ( Thomas Holding ) into marriage and he takes her to Egypt to live. Tired of her simple husband, Bella becomes involved with brutish Baroudi. To get rid of Nigel, she begins slowly poisoning him. However, Nigel's friend Dr. Isaacson arrives in time to save him. Now Baroudi wants nothing to do with Bella, and neither does her husband. Totally alone now, the distraught Bella wanders off into the desert and dies.—Pamela Short

The exploits of Bella Donna, an English adventuress, are matters of common gossip in London. Despite the fact that her reputation is distinctly unsavory, the Hon. Nigel Armine, an impressionable and rather sophisticated man refuses to believe what he hears. Struck by the marvelous beauty of the woman he marries her and takes her to Egypt. But the simple-minded Armine soon palls upon this roving restless spirit which fastens upon a handsome native Baroudi, as the object of its fierce and hungry adoration. The clandestine love affair increases in intensity until Baroudi so masters Bella Donna that he persuades her to poison her husband and she places small doses of sugar of lead in Armine's coffee. Day by day Bella Donna watches the deadly effect of her work as her husband grows steadily weaker. Just as his rapidly weakening condition holds forth the promise of quick release from her irksome ties Dr. Isaacson, an old friend of Armine, arrives on the scene. In the battle of wits between these two instinctive enemies, the doctor is the victor and he discovers what Bella Donna is doing. He denounces her to her husband and is ordered out of the house for his pains. Armine, innocently wishing to explain his action to Bella Donna, tells her tenderly of the attack which Isaacson has made upon her and assures her that he does not believe it. It is too much for Bella Donna's frayed nerves. Her hate for this insipid man has increased with every day and now that her plot has been frustrated and her dream of freedom shattered, she loses control of her temper and pours upon the astonished head of her husband a torrent of abuse which culminates in the startling statement that she is sick of him and is going back to Baroudi. Put when Bella Donna arrives triumphantly at Baroudi's she is stunned by her lover's statement that she is too dangerous a toy for him. His door closed upon her, she totters falteringly back to the house which she had so dramatically spurned. But she is met by her old enemy, Dr. Isaacson, who shuts the door in her face before she has an opportunity to reach her impressionable and soft-hearted husband. With the only two havens of refuse closed, Bella Donna, her wild dream of wealth, power and luxury shattered forever, gazes wistfully out upon the desert waste in the black night. Then she slowly traces her weary and faltering way out across the desert and into oblivion.—Moving Picture World synopsis