Todd Armstrong character Jason
Nancy Kovack character Medea
Gary Raymond character Acastus
Laurence Naismith character Argos
Niall MacGinnis character Zeus
Michael Gwynn character Hermes
Douglas Wilmer character Pelias
Jack Gwillim character King Aeetes
Honor Blackman character Hera
John Cairney character Hylas
Patrick Troughton character Phineas
Andrew Faulds character Phalerus
Nigel Green character Hercules
John Crawford character Polydeuces (uncredited)
Ferdinando Poggi character Castor of Sparta (uncredited)
Ennio Antonelli character Dmitrius, Drummer on Argo (uncredited)
Harold Bradley character Guard in Palace (uncredited)
Aldo Cristiani character Lynceus (uncredited)
Eva Haddon character Medea (voice) (uncredited)
Doug Robinson character Eupaemus (uncredited)
Davina Taylor character Briseis (uncredited)
Tim Turner character Jason (voice) (uncredited)
