TREKCORE > DS9 > EPISODES > BLOOD OATH > Behind the Scenes
 

	Alexander Siddig (Dr. Bashir), Colm Meaney (Chief O'Brien) and Cirroc Lofton (Jake Sisko) do not appear in this episode.
	Peter Allan Fields' original story did not feature Kang, Kor, and Koloth. They were to be new characters, but Robert Hewitt Wolfe, a big fan of the Original Series, suggested using the three most popular Klingons from that series. .
	Before the episode entered production, Junie Lowry-Johnson and Ron Surma checked to see if Ansara, Colicos and Campbell were still acting. They found the first two easily, but had difficulty finding William Campbell. He was actually doing Star Trek cruise conventions at the time.
	Fields based the episode on Akira Kurosawa's film Seven Samurai and John Sturges' remake of that film, The Magnificent Seven.
	Fields modelled Koloth after James Coburn's character of Britt and Kang after Yul Brynner.
	Kor was based on William Shakespeare's character of Falstaff, who appeared in Henry IV, Part II.
	The production staff toyed with the idea of having the three Klingons appear as they did in TOS, but decided against it.
	When Michael Ansara asked why the Klingons now looked different, he was told it was "a natural physical metamorphosis".
	The interior of the Albino's fortress was built on Paramount Stage 18.
	The Albino's fortress was actually a house in Pasadena designed by Frank Lloyd Wright. A model of it, which was blown up to show the destruction of the Compound, was built on Paramount's Van Ness parking lot.
	To set the mood for the fight sequence, director Winrich Kolbe had Wagner's Götterdämmerung played.
	This episode, originally titled "The Beast", "reunites" three Klingons from the Original Series: Kor ("Errand of Mercy"), Koloth ("The Trouble with Tribbles") and Kang ("Day of the Dove").
	John Colicos reprises his role as Kor in season four's "The Sword of Kahless" and season seven's "Once More Unto the Breach".
	The late Christopher Collins (Head Guard) previously played Durg in "The Passenger".
	This episode marks the deaths of Koloth (William Campbell) and Kang (Michael Ansara), although, Kang would later reprise the role in Voyager's "Flashback".
	William Campbell said of this episode it was his most difficult acting job, and one he would have liked to do again.
	Michael Ansara appears in DS9 again, as Jeyal in "The Muse".
	When Kor pulls open the holosuite door at the beginning of the episode, the "whoosh" sound of the Original Series doors is played.
	Andy Mangels and Michael A. Martin's Star Trek: Excelsior novel "Forged in Fire" is said to be a prequel of sorts to this episode.
	Michael Ansara on playing Kang: "He was one of the best characters I've ever played. I loved doing it, although I was surprised when they called us. Obviously things have changed over the years, and the look of the Klingons has changed. We tried to get an explanation and they told us, 'Well, Klingons lives to be very, very old and that's a natural physical metamorphosis!'"
	Terry Farrell on Dax and the Klingons: "With Kor, I had to convince him that he was a hero, and that tin my eyes he would always be a hero, so that was philosophical. With Koloth, I had to prove that I was strong enough to go into battle with him, so that was physical. And with Kang, I had to prove to him that my desire and need to be a part of this blood oath was strong enough that I could not imagine staying behind, that I was mentally strong and capable enough. So I had to exhibit the honor, the physical strength and the mental perseverance to go with them."