Will Dr. Horrible do whatever it takes to join the Evil League of Evil? Will Penny succumb to the charms of handsome, but intensely cheesy Captain Hammer? Hopefully we’ll all know tomorrow, when the third and final act of Dr. Horrible’s Sing-Along Blog is unveiled.

If you’re not familiar with Joss Whedon’s latest exploration of musical fantasy, run — don’t walk — to this web-only event and catch acts one and two. Neil Patrick Harris plays the introverted but committedly evil scientist Dr. Horrible, and Nathan Fillion hams it up as the superheroic and superficial Captain Hammer. Felicia Day innocently shines as Penny, a homeless advocate for whom the Doctor pines, and who is “saved” and wooed by the Captain.

After this weekend, this comicbook musical will no longer be offered for free on the site, but never fear… it’s destined for DVD in the near future. So don’t forget to support this quirky endeavor when you can, but run go watch it now!