"Sandcastle Royale" is an episode of Special Agent Oso.
While Oso and Wolfie lumber through the forest following Agent Lead Researcher's footprints, a special alert is called and Oso slips. A girl at the beach, named Katie, is going to build a sandcastle as a surprise for her mother, only she doesn't know how. It will be up to Oso to help Katie make the sandcastle before her mother finishes reading her book.
- The episode's title is a reference to the James Bond film Casino Royale.