The Open Door

Old Silas Blackburn, a wealthy recluse, lives alone with his butler and his ward Katherine. One night, Katherine discovers Silas murdered in the room where three generations of Blackburns have mysteriously died. Silas' grandson Robert, whom Katherine loves, comes to visit the next day, suffering from amnesia.

A man and two women, suspected of stealing bonds, are traced to a country hotel. While Judith, one of the women, is out horseback riding, the other two, Walter and Vera, are arrested. When, during a storm, Judith is injured in a fall from her horse, Boone Pendleton comes to her rescue. Soon the river becomes impassable, and they are trapped in Boone's cabin, where the two fall in love.

The household of Senator Walker consists of himself, his ward, Mary, and his nephew, Herbert. The other members of his household are John, an old servant, Lucy the maid, and a half dozen more servants. John is smitten with Lacy. She doesn't take him seriously, owing to the difference in their ages. Mr. Walker, rather old and feeble, draws up his will and leaves the bulk of his property to Mary and Herbert. He bequeaths $5,000 to his faithful servant John. Herbert is very fond of his uncle. The old gentleman is very much attached to Mary and very desirous that she and Herbert should be wed at the proper time.

Edith Sturgis, the daughter of a judge, returns from studies abroad to find her widowed father remarried. The new Mrs. Sturgis does not reveal that she has a son Dick, once unjustly jailed by Judge Sturgis, but now working as a reporter while still maintaining an association with the Brownlow gang. Quarrelling with her stepmother, Edith leaves home, meets Dick and falls in love.

At the death of Count de Beaulieu, his daughter Jeanne learns that her father had been the arch-criminal known as The Phantom. The only other person who knew her father's identity was his lieutenant, Franz Leroux, who now demands that Jeanne marry him in return for his silence.

Louis and August Siever, the twins sons of a German father and American mother, are traveling in Europe when war breaks out. August joins the Kaiser's army, but Louis, a supporter of the United States, is practically made a prisoner in Berlin for a year while he tries to prove his American citizenship. After a violent confrontation with Louis, August steals his brother's passport and leaves for New York with Gerda Anderson, a German spy.

Rosalind Joy (Helen Foster) is an heiress who has inherited a South Seas island known as Pleasure Island. A hidden cache of gold is allegedly buried on the island, which has several haunted structures. Rosalind's uncle, Spring Gilbert (Al Ferguson), wants the gold for himself and declares he will stop at nothing, not even the death of his niece, to get it. Rosalind, meanwhile, is befriended by Jerry Fitzjames (Jack Dougherty), a playwright. Unfortunately, Jerry has only recently escaped from a psychiatric hospital. Although he swears to protect Rosalind, she doubts Jerry's sanity. The two lovers race against Uncle Gilbert (who has set several traps for them) to find the treasure. In the end, Rosalind and Jerry are aided by the "Phantom Rider," a spectral horseman.

Police headquarters has been plagued by a series of robberies, culminating in the theft of a priceless necklace smuggled from Europe. The detectives are on the track of a gang led by master thief Ramon Mordant and his accomplice known as "the Face" because of his twisted and hideous countenance.

A gang of crooks are employed to get possession of valuable papers of international importance, held by the French Ambassador, Vicomte de Jarlais. They are also instructed to get the Ambassador out of the way and make it appear that he has committed suicide. His mysterious disappearance arouses the United States Secret Service officers

Two men, one of them a villainous hypnotist, contend for the same woman, unaware that she suffers from dual personality disorder.

Chaney plays two roles: mad scientist Arthur Lamb and Lamb's "experiment", known only as the Ape Man. This hideous creature was the result of Lamb's attempts to transplant animal glands into human beings. A lost film.

Winthrop Clavering a mystery writer, is continually ridiculed for the fiction of the crimes he depicts, so he decides to solve a case himself. To that end, he determines to find the slayer of Pedro Alvarez, who whispered before dying that his assailant was a woman. At the City Refuge for Homeless Girls, Clavering obtains the assistance of Margaret Holt, the sister of Victor Holt, the district attorney. Margaret, it is revealed, was abducted by Juanita, a member of a gang of white slavers led by Alvarez. After escaping from a brothel, Margaret became Alvarez' stenographer, hoping to gather secret information on his gang. While searching for evidence, Margaret was surprised by Alvarez, whom she killed. Finally, Clavering captures the gang, clears Margaret, and encourages her romance with cub reporter Jack Howell. This film is presumably lost.

Guido, an artist, is obsessed with the desire for the death of Clavering, a rich man who has entered into a forced marriage with Margaret, the girl whom Guido loves. The thought accompanies him in his work, his sleep and fills his every moment. One night, he awakens from a dream in which he has murdered Clavering. The next morning, Clavering is found murdered and Guido labors under the uncanny feeling that he is the murderer. Hoping to relieve Guido's fears, Margaret induces him to paint the picture of his dream. Clavering's butler sees the painting of his dead master, and is so horror stricken that he confesses to murdering Clavering for his money.

In Dijon, Inspector Hanaud investigates Betty Harlowe after her uncle, Boris Waberski, accuses her of poisoning her wealthy aunt for an inheritance. While an initial autopsy finds nothing, Hanaud discovers the use of Strophanthus Hispidus—a rare, undetectable poison applied via an antique arrow. Amidst a flurry of "poison pen" letters and deception, Hanaud proves the murder occurred despite the lack of conventional medical evidence.