Flat Stanley. His Original Adventure!

Stanley Lambchop is an ordinary boy. At least he was, until the night his bulletin board fell off the wall and flattened him. All of a sudden, Stanley can slide under doors, mail himself across the country in an envelope, and fly like a kite ! But flatness has its serious side, too. Sneak thieves have been stealing paintings from the Famous Museum of Art, and Stanley knows he's the only one who can stop them.
Will the robbers discover Stanley's plan before he foils theirs ?