Daniel Baldwin played Paul Delano, a corrupt cop—like his brother Frank Delano (who killed Chin Ho Kelly's wife). Appearing in "Poina 'ole" (Episode 12, Season 5), Five-0 thought someone was gunning after Paul because of his connections to a criminal organization that he was supposedly running from inside prison. It turned out he was just running his mouth.
You can watch every episode of Hawaii Five-0 on CBS All Access. Click the links above to go right to the episode.