In Dr. Horrible’s Sing-Along Blog, the titular character, Dr. Horrible (Neil Patrick Harris), is a self-proclaimed “horrible scientist” who creates a wildly popular online blog to share his wacky science experiments with the world. One of the recurring characters on Dr.
Horrible’s blog is Penny (Katie Holmes), a young woman who, despite being terribly average, falls in love with Dr. Horrible and becomes one of his biggest fans.
While it is never explicitly stated who played Penny in Dr. Horrible’s Sing-Along Blog, it is highly likely that Katie Holmes played the role. Holmes is well known for her role as Penny on the popular TV show Ally McBeal, which aired from 1998 to 2006, and she reprised her role for several cameos in subsequent episodes of Dr. Horrible’s Sing-Along Blog. Additionally, Holmes has made references to her character on Dr.
Horrible’s blog in interviews and during live performances of the show; for example, when she appeared on Jimmy Kimmel Live! in January 2012 and performed a song from the show called “Penny Loves Dr. Horrible.” Therefore, it is highly likely that Holmes played Penny in Dr.