Even though it's the third movie in the Blade series, this was the first movie to have the Marvel Studios logo at the beginning of the movie (Blade is a Marvel comics superhero).
After this film, the live action film rights went back to Marvel Studios.
An early idea by David S. Goyer for the film was to be set many years after the events of Blade II (2002), where vampires finally had achieved world domination and enslaved all humans, with Blade being the last hope for humanity. Blade's slower aging could be explained by his vampire blood. The storyline was deemed too dark and was later dropped.
Having just been saved by the Nightstalkers, Blade ridicules his rescuers as "rookies" and asks them if they think of the vampire hunt as a "sitcom". At that moment, the camera cuts to Patton Oswalt, who had been a cast member of the sitcom The King of Queens (1998) for several years. In addition, Ryan Reynolds was one of the stars of Two Guys, a Girl and a Pizza Place (1998) and Jessica Biel played one of the daughters in 7th Heaven (1996).
Abigail Whistler was created exclusively for the film, much like Whistler himself was for the original. Although Whistler did appear in the Spider-Man: The Animated Series before his film appearance. Goyer claims that Whistler was taken directly from him, right under his nose.
A private detective making a modest living, King was bitten and killed by the vampire Deacon Frost while on a case in London, England. Waking up to find himself one of the undead, King is horrified at what he had become and vowed never to consummate the curse by passing it to another. Thus, King subsists on blood purchased (or stolen) from blood banks and consuming only corpses or animals.
When Hannibal King is telling Blade about the return of Dracula, he shows Blade a copy of Tomb of Dracula #55. Marvel's "Tomb of Dracula" comic was the early-1970s title which included the first appearances of Blade (#10) and Hannibal King (#25), both written by Marv Wolfman.
As a vampire, he first battles Dracula, the Lord of Earth's vampires. While searching for Deacon Frost, King eventually meets Blade, the vampire hunter, whose mother had been killed by the same Deacon Frost. Initially distrustful of each other, they nevertheless team up to destroy Frost.
The vampire "final Solution" in this film originally came from an idea in Blade (1998), the first film in the trilogy. In a deleted scene Deacon Frost shows Karen Jensen a prototype of harvesting human bodies. This can be found on the "Blade" DVD.
When Blade and Whistler return to find Sommerfield dead, the phrase "Immortality will come to such as are fit for it" is painted in blood on the shower curtain. This is a quote by Ralph Waldo Emerson. The full quote reads: "Immortality will come to such as are fit for it; and he who would be a great soul in the future must be a great soul now."
The sets used as the vampire's high-rise lair are still in use in the sci-fi TV show Stargate: Atlantis (2004).
Jessica Biel inadvertently destroyed a camera, costing more than $300,000, when she fired an arrow directly into the camera's lens. She was directed to "aim for the camera", which had a Plexiglas shield in front of it to protect it, except for a small opening in front of the lens. Biel had perfected her archery skills while training for this role to such a degree that when she fired the arrow - at a distance of approximately 50 feet - at the camera, as she was directed, it went directly through the lens and into the camera itself, destroying it. The footage of the incident is included in the DVD extras.
Apart from the running powerslam move, Ryan Reynolds (who played Hannibal King) took the brunt of Triple H's wrestling moves, refusing to allow a stuntman to "do his job."
Dominic Purcell (Drake) did all of his stunts in the sword fight sequence against Blade.
Through King, in turn, Strange learns of the apparent return of Dracula. King, with vampire hunters Blade and Frank Drake, join Strange in their visit to Castle Mordo where they retrieve the Darkhold. They battle Dracula and the Darkholders, and then use the book to cast the Montesi formula. This spell destroys Dracula and all current vampires then on Earth and prevented any more from being able to exist on Earth. King was not destroyed by the Montesi formula because he had never taken blood from a living human being, but still required Doctor Strange to perform a complete blood transfusion for King to survive, which restored him to human form.
Apparently, discord amongst the three friends causes Drake to leave the firm, after which Blade suffers a breakdown after a fight with a once again resurrected Dracula. Dracula's return was a sign of the weakening of the Montesi formula. King is unable to continue operating the agency on his own, as he knows his vampirism is returning. After an examination, Doctor Strange concludes that King, because of his recent reversion, had become a "neo-vampire", a special type of vampire with all the abilities and weaknesses of the vampire, yet merely craving blood despite not needing it to survive. Strange manipulates the three men into reuniting under the name Nightstalkers to combat the supernatural enemies that were emerging. In their first mission, the Nightstalkers are hired by Lilith, the daughter of Dracula, to kill the Daniel Ketch Ghost Rider and John Blaze, and battle the Meatmarket. Alongside Ghost Rider, Blaze, Morbius, Doctor Strange, and the Darkhold Redeemers, the Nightstalkers battle Lilith and her Lilin.