Katie Cassidy (born November 25, 1986) is an American actress. After initially appearing in minor television roles, she made her film debut in When a Stranger Calls (2006). During the same year, she also had her first starring role as Kelli Presley in Black Christmas (2006). In 2007, Cassidy gained attention for her role as Ruby on the supernatural-horror television series Supernatural, during its third season. She later had a supporting role in Taken. In 2009, Cassidy became a cast member of the series Harper's Island and Melrose Place, both of which lasted for only one season. During 2010, she had a supporting role as Kris Fowles in A Nightmare on Elm Street and a recurring role as Juliet Sharp during the fourth season of the CW teen drama Gossip Girl. Cassidy had her breakthrough in 2012, after being cast as Laurel Lance / Black Canary, one of the main protagonists on the television series Arrow, which spawned an entire franchise known as the Arrowverse. Cassidy reprises her role in The Flash, Legends of Tomorrow and voiced the character in the animated web series Vixen. Following her character's death, Cassidy began playing Laurel Lance / Black Siren, an antagonistic version of her character from a parallel universe, starting in The Flash and continuing on to Arrow. In 2003, Cassidy made her television and acting debut appearing in an episode of the Lifetime drama series The Division. Cassidy has continued to guest appear in television shows such as Celebrity Apprentice 4, Listen Up! and New Girl. In 2005, Cassidy appeared in a recurring role on The WB's series 7th Heaven over the course of four episodes. That same year, she also appeared on the UPN teen drama series Sex, Love & Secrets. In 2006, Cassidy made her film debut as Tiffany Madison in the horror film When a Stranger Calls. Cassidy has gone on to have notable supporting roles in films Click, Taken and Live!. In February 2006, Cassidy was cast as Kelli Presley in the Dimension Films horror-slasher film Black Christmas, a remake of the 1974 film. The film centers on an escaped maniac who returns to his childhood home on Christmas Eve, which is now a sorority house, and one by one kills all of the sorority sisters. The film was released on December 15, 2006 to negative reviews from critics. The film was a moderate success, making over $50 million worldwide. In 2007, Cassidy appeared on The CW's supernatural drama series Supernatural. Cassidy played the role of Ruby, a demon. Making her debut in the show's third season, Cassidy appeared in six episodes. In 2008, though her character returned for the show's fourth season, Cassidy was replaced by actress Genevieve Cortese. In October 2008, Variety announced Cassidy had been cast on the CBS horror mystery limited series Harper's Island. Cassidy portrayed the role of Patricia "Trish" Wellington, a bride-to-be. The series centered on a group of family and friends who gather for a wedding on an island known for its sinister past full of gruesome murders. In each episode, at least one character is killed off. Cassidy and her fellow cast members were not told about their characters' deaths until the day they received a script. The series premiered on April 9, 2009 to 10.21 million viewers. Despite ratings failing to maintain the pilot's success, CBS aired the remainder of the series with the series finale airing on July 11, 2009.

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