Stella Maris (Mary Pickford) was born paralyzed and is unable to walk. Her wealthy parents try to prevent her from being exposed to all the bad that is happening in the world. She is not allowed to leave her room in a London mansion and is bound to her bed. Her door even has a sign on it which says: "All unhappiness and world wisdom leave outside. Those without smiles need not enter."  Stella has no idea a war is going on in the world and that there are poor and hungry people.
John Risca (Conway Tearle) is a well-known journalist and a friend of the family. He has been unhappily married to Louise for six years now and frequently visits Stella. John wants Stella to think he is perfect and lies about being married. Louise, meanwhile, wants a servant in her house and hires orphan Unity Blake (also Mary Pickford). Unity is uneducated and has been deprived and mistreated for her entire life. This resulted in her being afraid of everyone.
One night, a drunk Louise gives Unity the order to get some groceries from the supermarket. Unity does as told and on her way back, the food is stolen by kids. She returns to the home only to get beaten up by an outraged Louise. Unity is severely hurt and Louise gets arrested. It is announced she will have to serve three years in prison. John is kinder to Unity and adopts her. Unity is very grateful and falls in love with him. John himself is only interested in Stella. John wishes Unity to be raised at the Blount's residence, but they don't want her. They prevent her from meeting Stella, fearing Stella will notice there are suffering people in the world. They finally convince John to raise Unity at Aunt Gladys' house.
In order to make John fall in love with her, Unity starts to educate herself. Meanwhile, Stella gets an operation and is able to walk after three years. She meets John and they fall in love. One day she decides to give John a surprise visit. Louise, who has just been released from jail, opens the door and tells Stella the truth about her marriage. Stella is heartbroken.
Meanwhile, Unity wants to do John a favor by killing Louise. She realizes she and John never can be a couple and writes him a note which says he should get together with Stella. She next kills herself, making the police think it was a revenge murder. John is reunited with Stella and they marry.
- Mary Pickford - Miss Stella Maris/Unity Blake
- Ida Waterman - Lady Eleanor Blount, aka Aunt Julia
- Herbert Standing - Sir Oliver Blount
- Conway Tearle - John Risca
- Marcia Manon - Louise Risca
- Josephine Crowell - Aunt Gladys Linden