John (Alan Ladd), a blacksmith and swordsmith, is tutored at Camelot. As a commoner, he can't hope to win the hand of Lady Linet (Patricia Medina), daughter of the Earl of Yeonil (Harry Andrews), so he creates an alternative secret identity as the Black Knight. In this new role, he is now able to help King Arthur when Saracens and Cornishmen— disguised as Vikings— plot to take over the country, with the pagan King Mark intending to overthrow Christianity. However, John's thoughts are not only on the protection of England when the good Lady Linet becomes threatened— in fact, a scene of pagan sacrifice at Stonehenge shows that the ancient monument was ultimately destroyed on the orders of King Arthur to eradicate paganism and uphold Christianity. When conspirators within Camelot plan to use the "Vikings" to overthrow King Arthur, the Black Knight is branded a traitor.Alan Ladd as John
Patricia Medina as Linet
André Morell as Sir Ontzlake
Harry Andrews as the Earl Of Yeonil
Peter Cushing as Sir Palamides
Patrick Troughton as King Mark, portrayed as a pagan looking to overthrow Christianity and King Arthur
Anthony Bushell as King Arthur
Bill Brandon as Bernard
Ronald Adam as the Abbott
Jean Lodge as Queen Guinevere
John Laurie as John
Elton Hayes as the Minstrel
Laurence Naismith as Major Domo
This was the fourth film Alan Ladd made outside the US in order to qualify for a tax exemption. His fee was $200,000 as against 10% of the gross.
Filming started in September 1953. Shooting took place at Pinewood Studios and on location in Spain. Producer Irwin Allen called Spain "a wonderful country to make pictures in" because of its more than 2,000 old castles, twelve of which were used in the film.
Halfway through production, Bryan Forbes was called in to do some rewriting of the script (he is credited as "additional dialogue by..."). According to Forbes's memoirs, Alan Ladd's wife and long-time agent, Sue Carol, had script approval and objected to a scene where her husband's character stole a horse. 'During a script conference she repeated "Alan Ladd does not steal a horse, period. I'm telling you. He steals a horse, we lose the Boy Scouts Association and the Daughters of the American Revolution, to say nothing of his fan club." Irving [Allen], the senior producer was equal to the occasion and replied "He's not stealing a horse, Sue, he's borrowing a horse. You know like a Hertz car." "So, show me the difference" said Mrs Ladd, "You keep the stolen horse in and you start looking for another star because we're gonna be on the next plane home." "How would it be" I said, "if we kept all the action up to the point where Mr Ladd disposes single-handedly of the attacking Vikings, then he runs to a sentry and says "Is that the horse I ordered?" The sentry nods in agreement and Mr Ladd jumps on the horse and rides over the drawbridge?" "Yeah, I'll buy that" said Mrs Ladd and that is what we shot.' She also instructed Forbes when writing dialogue for Ladd to "keep him monosyllabic".
Donald Sinden, then a contract star for the Rank Organisation at Pinewood Studios, had a permanent dressing room in the same block as Ladd's. He said "(Ladd) brought in his entourage a double-cum-stunt man who bore an uncanny resemblance to him. The double did all the long shots, most of the medium shots and even appeared in two-shots when the hero had his back to the camera. The 'star' only did eleven days work in the entire film. He was extremely short in stature and unless he was alone, the camera could never show his feet, because if he was stationary he was standing on a box; if walking, the other actors were in specially dug troughs or ditches and for anything between, all other actors were required to stand with their legs apart and their knees bent."
The title tune for the film was "The Whistling Gypsy". For this purpose it was given new lyrics by its songwriter, Leo Maguire, and Elton Hayes, who sang it in the film.
One critic thought Ladd badly miscast, "playing the part like a tired American businessman prevailed upon to take the lead in a revival of Merrie England". By contrast Andrews and Bushell "played their parts for all and more than they were worth, giving every one of the pseudo-archaic line (e.g., 'Away with him, his presence doth offend our sense of honour') the full treatment: resonant Shakespearean delivery and Lyceum flourishes".
A lot of footage from this film was re-used in the low-budget, 1963 matinée film Siege of the Saxons, which is also set in Arthurian times. Even the outrageous (short-sleeved!) signature armour of the Black Knight reappears for continuity's sake.