The story of "Captain Thunder and the Holy Grail" is set during the Third Crusade in Palestine, when Captain Thunder finds in the dungeons of a fortress a dying Christian named Juan de Ribera, who entrustes him the mission to restore to Spain a cup which is the Holy Grail, stolen from an ancient order. Thunder, with his inseparable friends Crispin and Goliath, and a Viking princess named Sigfrid, will face an evil feudal lord and his black "devils", who are terrorizing the population of low Aragón.
| Directing | Antonio Hernández | Director |
| Camera | Javier Salmones | Director of Photography |
| Sound | Luis Ivars | Music |
| Writing | Pau Vergara | Writer |
| Editing | Iván Aledo | Editor |
| Art | Alejandro Fernández | Art Direction |