Tania Raymonde Helen Katz is an American actress. Her roles have included Cynthia Sanders on the Fox sitcom Malcolm in the Middle between 2000 and 2002, followed by the Alex Rousseau in the ABC series Lost from 2006 to 2010. She has appeared on MTV's Death Valley (2011), in the horror film Texas Chainsaw 3D (2013), and in the title role of the TV movie Jodi Arias: Dirty Little Secret (2013). In April 2015, she joined the cast of the TNT series The Last Ship. From 2016 to 2021, she starred in the Amazon Prime Video series Goliath.

Lost is an American science fiction adventure drama television series created by Jeffrey Lieber, J. J. Abrams, and Damon Lindelof that aired on ABC from September 22, 2004, to May 23, 2010, over six seasons and 121 episodes. It contains elements of supernatural fiction, and follows the survivors of a commercial jet airliner flying between Sydney and Los Angeles, after the plane crashes on a mysterious island somewhere in the South Pacific Ocean. Episodes typically feature a primary storyline set on the island, augmented by flashback or flashforward sequences which provide additional insight into the involved characters.