Amanda Walsh (born October 3, 1981, in Rigaud, Quebec, Canada) is a Canadian actress, writer, and former VJ for the Canadian television station MuchMusic. She began working as a professional actor at age twelve, attended Hudson High School in Hudson, Quebec, and won a gold medal at the 2000 Improv Games in Quebec as a member of the "8 People" troupe. She hosted or co-hosted several MuchMusic programs including Much Top Tens, Electric Circus, MuchOnDemand, and Fandemonium before leaving in 2004 to pursue an acting career in Los Angeles. Walsh is perhaps best known for playing Katie in the unaired pilot of The Big Bang Theory (2006), a role that was ultimately reworked into Penny, played by Kaley Cuoco. Her other notable television credits include a starring role as Jenna Halbert in Sons & Daughters (2006–2007, ABC, 11 episodes), appearances in Smallville, Veronica Mars, NCIS, Grimm, Two and a Half Men, Lost Girl (2014–2015, 9 episodes as Zee/Elizabeth Helm), Dirk Gently's Holistic Detective Agency (2017, 10 episodes as Suzie Boreton), and Curb Your Enthusiasm (2017). She also served as a story editor and wrote an episode of Schitt's Creek, and more recently appeared in Pretty Hard Cases (2023) and Brilliant Minds (2026). Her film credits include Disturbia (2007, as Minnie Tyco), Ghosts of Girlfriends Past (2009, as Denice the Bridesmaid, starring Matthew McConaughey), These Girls (2005, starring David Boreanaz), Full of It (2007), Man Maid (2008), WarGames: The Dead Code (2008), and Doula (2022).