Ricardo Castillo was 23 when he disappeared on August 31, 2007, after visiting relatives in Mexico. He had lived in the United States for eight years and was reportedly returning to the U.S. when he vanished. His last known contact came before an attempted border crossing back into the United States; after that, no one has seen or heard from him.

Castillo is listed in NamUs and is described as a Hispanic male, 6 feet 1 inch tall, about 220 pounds, with black hair. Despite efforts to locate him, there have been no significant developments and the circumstances of his disappearance remain unclear. Anyone who knew Ricardo, saw him near the border around August 31, 2007, or has information is urged to come forward.