Joss Whedon Gives Update on 'Dr. Horrible' Sequel

The "Avengers" director says that there is "a bunch of songs and a few scenes" written.

Joss Whedon has a big-budget movie The Avengers coming out next year, but he's moving one step closer to making the sequel to the Internet sensation Dr. Horrible's Sing-Along Blog happen.

Dr. Horrible, starring Neil Patrick Harris, Felicia Day and Nathan Fillion, was released in parts on the Web in 2008. Ever since its success, fans have been wondering when the followup will come. In an interview with Yahoo, Whedon gave an update on the progress of the project.

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"We have been working on that for a while. It's been hard, because we all have jobs, and some of them are extremely taxing," Whedon said. "But we have had a vision of the thing for a while, we have been working on it, we have a bunch of songs and a few scenes. We need a little free time and right now that's plenty hard to come by."

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Whedon and company aren't necessarily hurting for work. Fillion currently stars in ABC crime dramedy Castle and Harris is part of an ensemble cast on CBS' How I Met Your Mother.

In fact, Whedon and Fillion wrapped principal photography on Much Ado About Nothing, a project that was kept under wraps until recently and that may be eyeing the festival circuit.