Twenty years after its debut, Buffy The Vampire Slayer has to be considered one of the greatest television series ever. Looking back on that March 10, 1997 premiere and the seven seasons of vampire-stabbing, Hellmouth-blocking, feminist-evoking, gender-trailblazing, and genre-busting that so gloriously followed, we thought it appropriate to celebrate the show’s special birthday today.

So watch the video above for our Top 5 reasons why the Joss Whedon-created series starring Sarah Michelle Gellar is one of the small screen’s all-time best — plus you don’t want to miss the insider insights of a very special Sunnydale guest.

If you are a Buffy fan (as everybody should be) you probably have a favorite episode. One of the most beloved and influential has to be Season 6’s “Once More, With Feeling,” when the whole show became a musical for the Scooby Gang. Besides the ingenuity on a series that already took music seriously, the legacy of that excellent Whedon-written and -directed episode can be seen today in the likes of Crazy Ex-Girlfriend and the upcoming musical crossover on Supergirl and The Flash, among other instances.

One of my favorite scenes from Buffy came at the end of Season 5, just before the show moved from the WB to UPN for its final two cycles. The Slayer was dead, and with the series’ typical wit and narrative dexterity, Ms. Summers’ grave read: “She saved the world a lot.”

Yes, Buffy did, and she gave TV some new life that resonates strongly in this era of Peak TV.

Watch the video above then tell us what your favorite Buffy episode is, and why the show still matters 20 years later.