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 entrusts 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.
Sergio Peris-Mencheta
Natasha Yarovenko
Adrián Lamana
Man Martínez
Gary Piquer
Luis Fernando Alvés
Natalia Rodríguez
Francisco Merino
Jon Bermúdez
Xabier Murua
Ramón Langa
Jennifer Rope
Jorge Galeano
Antonio Chamizo
Alejandro Jornet
Andrea Masulli
Asier Etxeandia
Roberto Álvarez
Alejandro Naranjo