Egypte, 11e eeuw. Wanneer een hongersnood het land teistert, komt het welvarende Andalusische koninkrijk Denia de sultan te hulp, die Denia uit dankbaarheid het meest gewilde en begeerde object in het hele christendom geeft.
Nee, helaas is Onyx: Kings of the Grail nog niet beschikbaar op Netflix in Nederland.
| Directing | Roberto Girault | Director |
| Sound | Carlos Lidón | Sound Recordist |
| Production | Óscar Cifuentes | Executive Producer |
| Writing | Luis Reneo | Writer |
| Costume & Make-Up | Alicia López | Hair Department Head |
| Production | José Jaime Linares | Production Director |
| Costume & Make-Up | Giovanna Ribes | Costume Designer |
| Writing | Roberto Girault | Writer |
| Production | Pedro Palacios | Executive Producer |
| Sound | José Luis Alcaine Bartolomé | Sound Designer |
| Crew | Miguel Olarieta | Special Effects |
| Costume & Make-Up | Sonia de la Fuente | Makeup Department Head |
| Sound | Eduardo Ortega | Original Music Composer |
| Art | Itziar Sagasti | Production Design |
| Writing | Margarita Torres | Writer |
| Production | Óscar Cifuentes | Producer |
| Camera | Rafael Bolaños | Director of Photography |
| Editing | Adoración G. Elipe | Editor |
| Crew | Valentín Diez Morodo | Thanks |
| Directing | Luis Reneo | Second Unit Director |
| Directing | Daniel M. Caneiro | Script Supervisor |
| Writing | José Miguel Ortega | Book |
| Visual Effects | Helmuth Barnert | Visual Effects Supervisor |
| Directing | Patricia Ordás | First Assistant Director |
| Lighting | Raúl Pavón | Gaffer |
| Camera | Jorge Casabán | Key Grip |
| Camera | Marco Mastropietro | Still Photographer |
| Writing | Margarita Torres | Book |
| Directing | Chris Downs | Second Assistant Director |
| Production | Carla Hool | Casting Director |
| Production | Eduardo Lis | Production Manager |
| Sound | Miguel Ángel Caprara | Foley Artist |
| Crew | Mabel Villagra | Technical Advisor |
