Season 4, Episode 1 - "The Origin of Donnie (1)"
18 August, 2001
Location: Borneo, IndonesiaThe Thornberrys are preparing for Donnie's ""birthday"" party in Borneo when one crisis after another happens. Grandma Sophie decides to visit the same day Nigel and Marianne must capture a wild orangutan on film or the foundation will cut their funding.
