Buffy the Vampire Slayer
Buffy may have been based on a movie but the series bears so little resemblance to the 1992 film that the latter been largely forgotten. And while there’s been talk of a reboot, it would be from the film not the series. So given that nothing's been heard about it for a couple of years, we'll disregard it for now.
But Joss Whedon created a whole universe, so there's plenty of room for more stories. There's already been a follow-up comic, after all.
Slayers rarely live that long, so a return for Buffy in her thirties would make an interesting story. Maybe she's become a single mother and has to juggle slaying with parenthood?
Would it work? With Whedon at the helm, yes. He's solidly proved he has the chops for film (you all saw Avengers Assemble, right?) Besides, if anyone else did it, his fans would be too angry to cope.
Who would play her? Sarah Michelle Gellar could return as an older, more jaded Buffy, with a new appreciation for what she put her mother through.