Jonny Quest Riddle of the Gold (1964–1965) Online
A long-dead mine in Jahilipur, India, suddenly spits out more gold that ever before, and suspicious Mr. Corbin of Intelligence One wants Dr. Quest to look into it. Turns out it's not gold but a rare metal called zanium. Only two scientists in the world can identify it - Dr. Quest and Professor Gunderson - and Gunderson died recently in a plain crash in Jahilipur. Or did he? With so many events and shady characters tied to Jahilipur, the Quest party investigates under the pretext of attending a tiger hunt with the local maharaja. Though outwardly welcomed, numerous attempts are made on their lives. Eventually, their suspicions of an old nemesis behind it all proves correct.
| Episode cast overview: | |||
 | Mike Road | - | Roger T. 'Race' Bannon (voice) |
 | Tim Matheson | - | Jonny Quest (voice) (as Tim Matthieson) |
 | Don Messick | - | Dr. Benton C. Quest / Bandit (voice) |
 | Danny Bravo | - | Hadji (voice) |
| Vic Perrin | - | Dr. Zin (voice) |
 | Daws Butler | - | Maharaja / Corbin / Gunderson (voice) |
 | Marvin Miller | - | Abdul Kaseem / Henchman (voice) |
 | Janet Waldo | - | Airport P.A. / Stewardess (voice) |
| Doug Young | - | Ali / Henchman (voice) |
First appearance of the series' recurring villain, Dr. Zin.
With this episode, Don Messick takes over from John Stephenson as the voice of Dr. Quest.