There is an unaired “Buffy” pilot — starring a different actress as Willow

Buffy the Vampire Slayer wouldn't be the same without its stars — Sarah Michelle Gellar, Alyson Hannigan, Nicholas Brendon and Anthony Head. But believe it or not, one key member of the Scooby gang almost wasn't in the hit supernatural series. An actress named Riff Regan was the original Willow Rosenberg.

Regan, who starred on Sisters as Young Georgie, was cast as Willow in the unaired Buffy pilot from 1996. The unaired pilot, which can be found here on YouTube, follows the same plot as "Welcome to the Hellmouth," the series premiere episode of Buffy that ultimately ended up airing on March 10, 1997. Buffy starts her first day at school — although her high school is called Berryman High, not Sunnydale High — and meets Willow, Xander, Giles and Cordelia. She initially tries to refuse her duties as the Slayer, but a dead body in the women's locker room leads her right back to fighting the dead who lurk in the shadows.

Watching the unaired pilot, it's clear that Regan's Willow doesn't have the same chemistry as the rest of the cast. Hannigan's portrayal of the character is more innocent, and viewers could get a sense of the long-standing history that she has with Brendon's Xander. Regan, on the other hand, seems stiff and timid. She has limited dialogue in the episode, but she just sounds bored and unfazed by the supernatural things around her.

Of course, Willow is not the only big change between the unaired pilot and "Welcome to the Hellmouth." Silicon Valley star Stephen Tobolowsky played Principal Flutie in the unaired pilot, but Feud actor Ken Lerner played Mr. Flutie in the actual series. There are also a handful of set differences. The school library in the unaired pilot has a spiral staircase and is missing the swinging doors with the circular window. Willow also gets attacked by a vampire in the school's theater, instead of the cemetery.

Watch the unaired pilot and compare it to "Welcome to the Hellmouth" before Netflix removes Buffy the Vampire Slayer from its catalogue on April 1.

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