Captain Spragot, blown out of his course, sights an uncharted island. He goes ashore and the island is so beautiful that he marks it on his chart. The Captain has promised his wife that this is to be his last voyage, but on his return the ship owners make him such a tempting offer that he signs a contract to make just one more trip. He so informs bis wife and his little daughter Jane, aged five years, and there is a stormy scene between husband and wife. 

As the Captain leaves the house, John Western, a friend, enters. He is secretly in love with the Captain's wife and she tells him that she will give her answer to his plea the day the Captain sails. On the day of sailing Captain Spragot's wife pleads with him to remain home. He refuses. Then it is that the wife agrees to leave with Western. Remorse overtakes the Captain on the deck of his ship and he returns home. 

Just as he arrives he meets his wife leaving with Western. Seizing his little daughter. Captain Spragot drives Western and the woman away. With his little daughter the Captain sets sail for his island. There he sends the boat on to her destination and decides to remain on the island forever. Jane, in the years that pass, becomes a beautiful girl. She discovers some diamonds buried in blue clay, but her father orders her to destroy them telling her they will bring her nothing but unhappiness. 

Ralph Ashton, a young society man, loses his inheritance and ships on a vessel as steward. He is a victim of shipwreck and is washed ashore on the island of Content. Jane, whose father has died, discovers the body and drags it ashore. They live alone on the island for a year and learn to love each other. One day in looking for an old coat, Ralph discovers the bag of diamonds. Until this time he has been contented, but from now on his one desire is to escape with the wealth. 

He spends hours watching for ships, and trying to polish the diamonds. Too late, Jane realizes that her father's words were partly true. Ralph neglects Jane. Then one day Ralph's signal is seen and they are rescued by a passing ship. While Ralph is overjoyed and mingles with the officers. Jane, unobserved, steals from the cabin and leaning over the stern, watches her beloved island disappear from view. The diamonds bring a small fortune to Jane and Ralph, who are now married. Jane cannot adjust herself to changed circumstances, and Ralph seeks for more congenial company. 

He becomes fascinated with Rosett Van Nott. Jane overhears the woman and her husband planning to elope. Jane is urged to secure a divorce, but refuses. Jane plots with a sea captain in an endeavor to save her husband. One night Ralph is overcome by assailants and chloroformed. He is taken aboard ship where Jane is anticipating his arrival. Ralph is kept drugged until the old Island is reached when he is carried ashore and placed in the old hut. When Ralph recovers consciousness he finds himself again on the Island of Content. He seeks Jane; his face softens and he holds out his arms to her.

—Moving Picture World synopsis