The Scarlet Slipper Mystery by Carolyn Keene

Schmidt had unwrapped the painting. It was another portrait of Helene Fontaine.
    “I bought this in a little gift shop out in the country,” he explained. “The girl who modeled for it looks very much like Madame Provak, a famous ballet dancer whom I saw perform many years ago, before the trouble in our country. I have not seen or heard of her since.”
    After a pause, the caller smiled and said to Nancy, “Do you mind if I ask why you are searching for paintings of a ballerina?”
    “I am an amateur detective, and my father is a lawyer,” Nancy replied. “We are working together on a case that involves the children of Madame Provak.”
    “You know them? Where are they?”
    Nancy told of her connection with Henri and Helene Fontaine. “The girl in this painting,” she went on, “is Helene, the daughter of the famous dancer you knew. Her parents passed away some years ago in France. Later, Helene and her brother were threatened and fled to this country.”
    Mr. Schmidt’s brow furrowed. “This painting is unsigned,” he said. “I am anxious to learn the artist’s name.”
    Mr. Drew nodded to signal to his daughter that he thought it would be safe to reveal the truth.
    “Henri painted it,” Nancy declared.
    The caller gasped. “Miss Drew, I must now tell you the strange story I mentioned over the telephone. As you know, I am an amateur artist. In examining this portrait closely, I discovered that two valuable gems had been hidden in the pigment that forms the ruffles of the ballet skirt. I was about to go to the police with my find when I happened to see your ad.”
    Nancy and her father exchanged glances. Each was thinking how careless the smugglers were, not to have removed all the gems!
    “Your find,” said Mr. Drew, “confirms a suspicion of ours that jewels were smuggled into this country from France by this method.”
    Mr. Schmidt jumped excitedly from his chair. “This may explain a great theft of gems from the leaders of the Centrovian underground movement.”
    Nancy and her father instantly thought of the jewels carried to France by the Provaks. Had some of these been stolen?
    Mr. Schmidt went on to say that the Provaks had had spotless reputations, so far as he knew. However, life might have become so hard for the brother and sister that they had resorted to thievery of the last of the jewels their parents had turned over to the Centrovian underground, and smuggled them into the United States.
    “Oh, I’m sure Helene and Henri are honest,” Nancy cried. “Mr. Schmidt, have you any idea who sold the painting to the gift shop where you purchased it?”
    The girl was elated when she heard that Mr. Schmidt had learned from the proprietor that the man had red hair.
    The conversation was interrupted suddenly by the arrival of Mr. Koff, who rushed across the room and clasped Anton Schmidt in his arms.
    “Anton!”
    “Johann!”
    Finally Mr. Koff turned to the others and said, “You must think we are very emotional, but this is a most happy occasion.”
    The Drews smiled understandingly. Then they told the story of Schmidt’s painting.
    “This does look bad for Helene and Henri,” Mr. Koff agreed. “It was for such things as this that I was so worried about losing my briefcase.”
    He explained the loss to his cousin and added, “I am afraid that letters in it that mentioned the stolen jewels have fallen into the thieves’ hands. They may be trying to shift the blame for the theft and the smuggling onto the Fontaines, and for the third time have frightened them away.”
    The new complications in the case worried everyone. But both Centrovians expressed a hearty certainty that the Fontaines would prove to be honest.
    “As evidence of my good faith,” said Mr. Schmidt, “I would like to leave this portrait and the gems here for safekeeping.”
    Although the Drews knew this might involve them more deeply in the situation, they agreed to be custodians of the articles.
    The next morning, Nancy